United Kingdom (1942-1943)
Semi-Amphibious Cargo Vehicle – 3 Prototypes Built
The Hexonaut’s story began between 1942 and 1943. Operating in Burma (now Myanmar) during the Second World War, the British ‘Forgotten Army’ – the 14th Army – had as much of an enemy in the harsh terrain of the land as they did in the Japanese soldier. Burmese terrain was rough to say the least, with dense jungle, marsh and swamp land, rivers, and large bodies of water everywhere. This harsh landscape was tough on vehicles, and narrow jungle trails made it hard for large cargo transport vehicles to navigate and reach troops with their precious supplies.
What was required was a smaller, all-terrain vehicle, small enough to navigate this terrain while still carrying a useful load. It was the venerable Humber company, no stranger to producing military vehicles for the War Office (WO), that believed they had just the vehicle for the task.
A British company, Humber had been in business since 1887. They initially produced bicycles, and later manufactured motorbikes and cars. In the early 1930s, they would become a subsidiary of the Rootes Group. With wartime, Humber pitched into the national effort, producing a number of highly successful wheeled armored vehicles. These included staff cars, the Humber Armored Car, the Light Reconnaissance Car, and the 8 cwt Cargo Truck, among others. General Bernard ‘Monty’ Montgomery would even have them specially modify two of their Super Snipe cars into armored staff cars and used them in North Africa and Italy.
General Bernard ‘Monty’ Montgomery in one of two custom-built Humber Super Snipe cars in Italy, 1943. Photo: Wikimedia Commons
Development
The vehicle Humber would come up with would be named the ‘Hexonaut’- presumably derived from the fact it had six wheels and nautical aspirations. The GS in the full name is a little harder to explain, as there is no record. One could assume it stood for ‘General Service’, but this is just speculation. Only three prototype vehicles were built. Most of the known detail comes from the surviving records and photographs of ‘Prototype No.1’. Any unique differences and updates made between the vehicles are sadly lost to history.
Humber had grand plans for their Hexonaut. Ideally, the vehicle needed to be small enough and light enough to fit in, and be carried by a C-47 Dakota transport plane. The ability to be parachute dropped was also desired, along with the ability to float. The vehicle was not a true amphibian, being designed with essentially deep-fording in mind, rather than traversing large bodies of water on the surface.
Head-on view of the Hexonaut showing its rather narrow silhouette. Note the central driver’s cab, with the exhaust on his left and the fuel tank to his right. The plate at the bottom covers the radiator for wading. Photo: Wheels & Tracks No. 35
Design Overview
The design of the Hexonaut consisted of a narrow space-frame hull some 4 ½ feet wide (1.35 m) with an overall length of about just under 11 ½ feet (3.50 m). The rear of the hull was square, while the front sloped inwards forming a bow. The vehicle was reasonably tall, at 7 ½ feet (2.30 m). Placed on the side of the hull were 6 large tractor-like wheels fitted with deep-treaded tyres and 6-wheel drive, mounted tightly with only a few inches between them. It is estimated that the vehicle weighed approximately 3-tons (3.5 tonnes).
The upper portion of the vehicle consisted of a forward driver’s cab with a windshield that could be folded down onto the sloping nose. To the rear of the driver was a large cargo bed about 6 foot (1.8 m) long sharing the width of the vehicle, with rigid side panels and a drop-down tailgate. Capacity was 1-ton of cargo or 8 troops. The roof of the vehicle consisted of a canvas cover supported by hoops and tied down to the bed. Transparent inserts were provided for the rear of the vehicle.
Hexonaut ‘Prototype No. 1’. With its 6×6 drive and narrow silhouette, it was definitely a unique vehicle among Humber’s other militaristic endeavours. Photo: Wheels & Tracks No. 35
Propulsion
Designers of the Hexonaut would employ a propulsion layout that would later appear on the Morris Company’s Terrapin ‘4-ton Amphibian’. A pair of Humber/Hillman 14hp, four-cylinder engines would be placed back-to-back in the lower hull. The forward engine (under the driver’s seat) powered the right 3 wheels, while the rear engine (under the cargo bed) powered the left 3 wheels and a winch for self-recovery. Both engines ran 4-speed Hillman gearboxes and transfer cases attached to the rear of each engine. A single gear stick controlled both gearboxes. The whole system shared one exhaust – to the left of the driver – and one radiator found in the nose. Fuel was carried in a small tank (capacity unknown) placed on the right of the driver. Provision was made for the stowage of two ‘jerry’ cans behind the driver’s head. However, on a later vehicle, this was replaced with an air cleaner system. Altogether, this system provided a blistering road speed of 20 mph (32 km/h) – this would of course be reduced off-road.
Hexonaut rolled on 6 large steel-disc wheels fitted with large, deep-cleated tires. There was no suspension, the wheel hubs being directly mounted to the final drive stations, which were bolted to the hull. Steering was achieved via tank-style tiller bars, and effectively used a similar ‘skid-steer’ principle. To turn right, for example, one would throttle up the left wheel’s engine and apply breaks to the wheels on the right – and vice versa. It was said that pulling hard on one stick while pushing hard on the other would let the vehicle make a sharp – almost – pivot steer. Six wheels provide a lot of ground friction, making turning difficult. It was found this could also stall an engine. To combat this, the middle wheel was minted ever-so-slightly lower than the fore and aft pair. While making pivoting easier, this had the unfortunate side-effect of creating a seesaw effect when driving on a hard surface. On soft ground, it was not a problem, as the wheels partially sank into the ground, canceling out the imbalance.
The power-train layout of the Hexonaut. The centrally aligned engines are clear to see, as are their drive shafts to the respective wheels. This diagram also shows the radiator at the front, and the powered winch at the rear. Photo: Wheels & Tracks No. 35
Mud-Skipper
Hexonaut was not designed to be ‘amphibious’ in the true sense of the word. It was not designed to float over large water bodies. Its design catered more to deep-wading, and the traversing of extremely muddy bog and swamp areas that a standard vehicle would likely drown in. Its boat-like bow would carve a path while its deep-tread tires would push it through the slop.
To keep the vehicle watertight and in-turn add flotation, gasketed steel plates would be tightly sealed against the radiator grill at the front of the vehicle and the open winch compartment at the rear. These plates were held in-place by tightened wing-nuts. When not in use, they were presumably stowed in the cargo bed.
Rear view of the Hexonaut. The transparent windows in the canvas roof are plainly visible. Note also the rear tailgate, and water-tight plate on the bottom of the vehicle. Behind this was the winch. Photo: Wheels & Tracks No. 35
That Sinking Feeling
Ultimately, the Hexonaut would prove to be something of a failed experiment. One major flaw was the steering system. It was found that any faults with the running of one of the engines – reduced speed, loss of power, full on stall – could catastrophically affect the steering. Depending on which engine had a fault, the vehicle could snap to one side. Given the vehicle was rather tall, narrow, and without seat belts, this could be highly traumatic for the driver. This could be considered not ideal.
The Hexonaut project ended before it had reached full development, and no more than the three prototypes were produced. One of these was tested by the Wheeled Vehicle Experimental Establishment (WVEE) at Farnborough (Hampshire, South England), but the outcome of these trials are unknown. It was still in military possession in June 1946, when it was displayed at an exhibition of military equipment and vehicles at the Fighting Vehicle Research and Development Establishment (FVRDE) in Chertsey (Surrey, South England). After this, the story of Hexonaut turns to mystery.
Life After Death
One of the Hexonaut prototypes did somehow survive, however. Whether this was the same vehicle seen at the FVRDE exhibition is unknown. The vehicle was acquired via Government Surplus Auction by one Mr. Stanward, and found civilian use in Somerset (Southwest England). Much of the superstructure was removed – but kept – and a large crane was added to the cargo bed. It was used to haul lumber until the mid-1950s.
The surviving Hexonaut as it looked while under civilian operation from the 1950s to 1970s. Note the addition of the large crane, itself powered by a third engine. The gentleman at the controls is Mr. Stanward of Somerset. Photo: Wheels & Tracks No. 35.
The vehicle was used hard and, in 1971, the vehicle changed hands again, this time falling into the collection of Geoff Theobald of Exeter. It was then later sold to Guy Arend of the Belgian Victory Memorial Museum, Arlon. Mr. Arend restored the vehicle to a semi-accurate state with what materials were available. Unfortunately, his museum went bankrupt in 1998, and the collection was spread around the world. The Hexonaut would not surface again until 2012, when it was put up for auction by RM Sotheby’s at The National Military History Center, Indiana, USA, on the 8th of December. It sold for almost $50,000 (almost £40,000 at that time). What happened to it after that is unclear, although it would now appear (as of 2024) that it belongs to the Wheatcroft Collection (Leicestershire, Central England). Quite a journey.
Conclusion
The ‘Hexonaut’ was little more than a private venture by Humber. A largely forgotten vehicle, it is by pure luck some original photos have survived. These were found in a clear out of Devonshire House in Piccadilly, London, once a headquarters of the Rootes Company. Rootes themselves practically ignored the vehicle, focussing more on Humber’s more successful military vehicles.
Nonetheless, the Hexonaut is an example of alternative thinking that – had it entered service – could have really found a use in the environment it was intended for. The Humber’s contemporaries, such as Morris’ Terrapin, would have a far more successful story, still, little vehicles like the Hexonaut should not be ignored as part of armored vehicle design history. It is lucky that one still survives, more than can be said for many other experimental oddities. Humber would continue to produce armored vehicles well into the Cold War era. The most famous of these are the FV1611 Humber Pig Armoured Car and FV1620 Humber Hornet Missile Carrier.
The surviving Hexonaut at the RM Sotheby’s auction in 2012. Photo: RM SothebyThe Humber Hexonaut GS 6×6. One of those unique military designs that was largely forgotten. Illustration by Pavel ‘Carpaticus’ Alexe, funded by our Patreon Campaign.
Specifications
Dimensions (L-W-H)
11ft x 4 ½ ft x 7 ½ ft
(3.50 x 1.35 x 2.30 m)
Crew
1 driver
Weight
Approx. 3-tons (3.5 tonnes)
Load capacity
1-ton of cargo/8 troops
Propulsion
2x Humber/Hillman 14hp, four-cylinder engines
Speed (road)
20 mph (32 km/h)
Sources
T.L.O. (Technical Liaison Office) Report No. 2 – 15th January 1944.
T.T.2 Technical Liaison Report No. 16 – November 6th 1944.
AFV Weapons Profile No. 21: Armoured Cars: Guy, Daimler, Humber, AEC, 1970
Wheels & Tracks Magazine No. 35, Pg. 15 – 19, 1991.
Stephen Lewis, Humber Cars: The Post War Years, Amberley Publishing, 2021 RM Sothebys
M.O.I. ‘Moveable Maginot’. Illustration by Henry Aponte.
United Kingdom (1941)
Mobile Fortress – None Built
In 1941, Britain had just dodged the bullet of a German invasion. The fears of an invasion peaked after defeat in France, but gave way in July and August 1940 to a sense of national defiance with air superiority over the UK maintained in the Battle of Britain. Although unable to return to France in 1941 to open a second front, Britain instead waged its war in North Africa.
At this time, Britain stood alone in Europe. France had collapsed, America still sat across the Atlantic watching, and the whole of Britain, its Empire and Dominion, had to be brought to bear to continue to war and fight it successfully.
To do this, a renewed national effort was needed in the UK, along with new weapons. What could embody this national need more than a new giant tank? To this end, in 1941, the Ministry of Information published some ideas for this renewed national drive to win, and it included possibly the most preposterously large and unwieldy tank imaginable – a literal ‘moving Maginot’.
Origins
The vehicle in question was pictured by an artist within a small pamphlet published by the Ministry of Information (M.O.I.) in 1941. The Ministry of Information was formed directly after the declaration of war on 3rd September 1939, with an official inception date of 4th September, and the first minister to oversee the department, Lord Macmillan, was appointed the next day.
The somewhat innocuous name belied its true significance and power. This Ministry had direct oversight over all news, censorship, and publicity with a goal of promoting the national case for war to the public. This was not a new idea. An M.O.I. had existed in WW1, but in this new war, its role under MacMillan was criticized. It was duly scaled back in 1940 with Macmillan being replaced by Sir John Reith, who in turn was replaced by Duff Cooper in May.
Cooper was replaced in July 1941 by Brendan Bracken, under whom it settled into its routine work with the same oversight but less direct censorship of the press. Under Bracken, the M.O.I. became less of an arm of state propaganda and instead, more towards a department focusing on ensuring secret information was not printed by mistake and on providing technical publications. The M.O.I. would be disbanded in March 1946.
The Pamphlet
Published by the M.O.I., ‘The Brains to Win’ was just 20 pages long and it was filled with photos and artwork. Artwork for the M.O.I. was produced mainly by a relatively small number of experienced artists, including Eric Kennington, Paul Nash, and William Rothenstein. Exactly which artist or illustrator was behind the Moving Maginot or from whose febrile imagination it was spawned is not known.
Title Page of the Ministry of Information pamphlet.
Source: The Brains to Win Two examples of other developments shown in ‘The Brains to Win’. A model of a new aircraft being tested in a wind tunnel (middle) and a concept for a new type of ‘streamlined battleship’ replete with guns big and small (bottom).
Source: M.O.I.
Although the pamphlet is undated, there are certain events mentioned inside which assist in dating it. For example, there is mention of the sinking of the Graff Spee (December 1939), and the battles of Britain (July-October 1940), Taranto (November 1940), and Cape Matapan (March 1941). Also mentioned is the raid of the Lofoten Islands (March 1941). The latest identifiable date is the mention of the sinking of the Bismarck. As that ship was sunk in May 1941, it means that the pamphlet cannot have been published before that date.
Not mentioned, but events which could have been referenced, would be the defeat of Italian forces and their surrender at Jimma (July 1941) and Gondar (November 1941), or the Relief of Malta (August 1941). Certainly it would be expected that the expansion of the war following Japanese attacks on British and American possession in the Pacific region in December 1941 would have been noteworthy.
A copy of the pamphlet held by Yale University is stamped as having been received into their collection on 1st October 1942, meaning it cannot have been published after that date. The omissions for other events in the second half of 1941, however, would tend to indicate that it was put together in the summer of 1941 and published before the end of the year dating the ‘design’ of the Moveable Maginot to 1941.
The zBrains to Winx covered aspects of aircraft development, promoting the Spitfire in particular, naval development, even advances in chemistry, and what we know today as RADAR. One of the small images in the pamphlet also provided a rather fantastical view of a giant tracked armored vehicle.
The Moveable Maginot.
Source: The Brains to Win
Design
It is difficult to adequately describe and convey the true scale or weapons on this colossal machine. There are plenty of clues to its scale from the tiny trees, to the silhouettes of the men on the ramp in the front, and aircraft on the roof. Suffice to say that such a vehicle conceived and constructed to such dimensions would be well beyond any capacity anywhere for transportation by train or road. It was wider than any road of the day, too high to fit under any bridge, and too long to negotiate any route through an inhabited area without causing untold damage to people, houses, livestock, and infrastructure. Assuming each of those silhouettes on the ramp is meant to represent an adult about 2 m high, then this machine could easily be 50 m high and 50 m or more long.
Operating on two pairs of tracks on each side, these tracks would ellipse the largest tracks ever built, those of the NASA crawler tractor measuring around 2.3 m wide per 5.5 tonne link or from the Bagger series of excavators at 3.8 m wide.
NASA Crawler Tractor CT-2. Built in 1967, this machine is the largest tracked vehicle ever made.
Source: NASA Bagger excavators in use, the size is put into context by the front loader next to it looking more like a toy than a large industrial machine in its own right.
Source: Wiki
The tracks as shown on this ‘Moving Maginot’ would appear to be in the 4 or 5 m wide range per link and there are two sets on each side. Even assuming just 10 tonnes per link and what appears to be around 80 links per set, meaning 800 tonnes just for one set of tracks. This vehicle has two on each side, meaning more than 3,000 tonnes just for the tracks alone before any consideration to the wheels, suspension, engine, armor, men, fuel, ammunition, or anything else.
The Moveable Maginot which, as drawn, despite its huge bulk, has not sunk into the ground at all.
Source: The Brains to Win
The general shape of the vehicle is little more than a gigantic brick. The entire body is roughly rectangular with a projection in the lower half of the front. In the bottom of that projection are a series of rectangular ramps, presumably to allow troops, guns, and maybe vehicles to be embarked/disembarked. On the front of this projection are three of the gun positions, each consisting of pairs of half-drum-shaped mounts with a pair of guns each. The central of these drums is positioned vertically for side to side rotation and is larger than the horizontally arranged drum-shaped positioned on each side of it allowing for elevation and depression. Above this projection on the front are four large circular structures which appear to be vents, but which are actually loudspeakers.
These would allow for both the broadcast of propaganda for anyone still in earshot or just to create “such a hideous din that the nerves of the opposing army will be shattered”. Above these noise-weapons was a vertical step surmounted by a smaller rectangular casemate from which presumably some command of the vehicle was meant to be exercised. On top of that was another turret and there was another turret on each side of this casemate. These three guns are pointed upwards in the picture to indicate a probable attempt to display some means of air defense for the vehicle.
Along each side of the rectangular hull was another projection reaching out part way over the top of the first set of tracks and somewhat reminiscent of the sponsons used on ‘Little Willie’ in 1915. On this projection, there would be four enormous drum-shaped turrets with the ones furthest fore and aft being larger than the central pair. Each turret had multiple guns and could rotate horizontally with some vertical movement allowed from the guns within the drums.
There is no view of the rear of the vehicle. There is also no view of the roof but there are two features drawn on top. The first most obvious one is the use of a pair of ramps from which aircraft are launched. Despite its leviathan size, the width would have been nowhere near sufficient for a conventional take off for an aircraft and the description provides the answer:
“… has aeroplanes which can be catapulted from the roof.”
This would be a steam catapult system as used on aircraft carriers and could accelerate the aircraft so that it would obviate the need for a runway. Lacking a runway, there would be no way to land back on the roof and this might be the reason for feature 2 – the large crane which could lift a landed aircraft back onto the roof. Whatever the thinking was, it was a poor scheme and an overly complex one, but it did, at least, look good as an illustration.
The final feature for description is the track unit. The huge tracks, as previously described, formed a simple rhomboid shape and extended in height to around half way up the machine. Each unit was made up from a pair of tracks and multiple road wheels and return rollers are evident reminiscent of some interwar medium tank designs. The road wheels were attached to a large spar across the bottom of the track unit which appears to have been drawn in the manner of such a unit holding individual springs etcetera as part of the suspension. Above this spar and covering the majority of the sides of the track run was a large armored panel which, thanks to the proportions of the tank, was big enough to house another pair of the large drum-shaped turret as mounted on the projection above them. Multiple rectangular portholes are provided on all faces of the vehicle and the entire structure is shown as being riveted or bolted together.
Propulsion
Moving a vehicle weighing several thousands of tonnes on land, even on its huge tracks, would be a challenge. There was no single land-engine which could possibly power such a machine. Weighing more than a naval destroyer, it would have to have reverted to using some naval system of propulsion like a steam boiler to enable it to move. Even then, this large mass, once moving would be a substantial problem to stop, especially on a slope so the engine would have to be extremely powerful to provide both control and a speed above that of a walking man. For reference, the NASA CT-2 moves at just 3 km/h. It is perhaps ironic that low speed and maneuverability were probably the only thing it would even have had in common with its namesake – the French Maginot Line.
Armament
A veritable Woolwich Arsenal on tracks , this machine is covered with guns and turrets. Command and control over so many guns would have been extremely complex as well as difficult and whatever crew such a machine would have needed just to move would be expanded by the crews for so many guns. The addition of guns and turrets everywhere and anywhere, the lack of centralisation of armament, is a characteristic often seen on these great idea-tanks.
Conclusion
This is quite obviously not a serious vehicle design. At the time of going to print in 1941, the new heavy or infantry tank was going to be a lot smaller in the form of the A.22 Churchill, but it would not be a legitimate expectation to see the next new tank published into the public domain where the Germans might be able to get hold of it.
Instead, this drawing was simply a vehicle to convey to the public that Britain was not standing still, it was no passive layer in the war and was instead, putting its full resources to work to design and develop new weapons with which to win the war.
Rather thankfully, this monstrous machine was not a real project. It was never going to get built and even if someone in government or even the Army had seen it with a real Archimedesian ‘Eureka’ moment, there is no plausible reality in which the Ministry of Supply would have authorized tens of thousands of tons of valuable steel, hundreds of guns, and planes for such a project.
Nonetheless, despite not being a ‘real’ project, this machine is still an interesting look at the portrayal of a new heavy tank at a period in the war when Britain was genuinely struggling to get new tanks made and when its industry and cities were still being bombed and battered by the Germans. The war would drag on for four more years and the sort of inventiveness and plucky resolve as a desire to resist and win as promoted by the pamphlet would come true in the end. This vehicle was simply a stepping stone on that journey for the public.
M.O.I. ‘Moveable Maginot’. Illustration by Henry Aponte.
There was a remote possibility that the 1939 British Expeditionary Force (BEF), sent to defend Belgium and France, could have been issued with the same Czechoslovakian-designed tank the Germans equipped their panzer divisions with and used during their May 1940 Blitzkrieg attack. The German’s designation for this tank was the Panzer 38(t).
TNH Tank
On 13th June 1939, the British War Office Mechanisation Experimental Establishment received a new Czechoslovakian tank by rail for examination and testing. It was manufactured by Českomoravská Kolben-Daněk (ČKD), which was based near the capital Prague, and called the Praga TNH-P 8-ton tank, or TNH. It was unpacked by ČKD company’s fitters who had accompanied the tank. The tank was completely equipped apart from the ammunition. ČKD were keen to sell its new tank to the British Army and other foreign powers.
This Czechoslovakian built Praga TNH-P 8-ton tank was sent to England for testing in June 1939. (MEE)
This tank was designed to replace the Czechoslovakian Army’s LT vz. 35 tank and also be an export success. By the time rgw TNH was tested in the UK it had already been sold to Iran, Peru, and Switzerland. Lithuania had also put an order in by this point. It had a roomier interior than the earlier tank and a different suspension system. It was armed with a Škoda 37 mm gun in the turret and had two 7.92 mm Zbrojovka Brno vz.37 machine guns, one in a hull mount and the other coaxial, mounted in the turret. The armor on the front was 25 mm thick and 15 mm thick on the sides. The armor on the test vehicle sent to the United Kingdom was made of mild steel, with the exception of the turret front, which was armored.
Observations
The Driver’s Position
The British inspection team first examined the driver’s position, noting that it was on the “off-side of the vehicle.” This was unexpected for a European tank, as most had the driver position on the left side of the tank and not on the right. That was the first ‘plus’ mark noted on the report card. Czechoslovakian drivers drove on the left side of the road, just like in Britain, until March 1939, when the commander of the German occupation forces ordered a change over to the right side of the road to conform with German traffic legislation.
The inspectors recorded that the driver’s seat was adjustable for length but not for height and that the angle of the backrest could be adjusted. When the front vision hatch was locked in the open position, the driver looked through an opening that was 8 inches (20.3 cm) wide by 4 inches (10.16 cm) tall. This gave an adequate vision arc of 120º. In wet or dusty weather, a temporary glass windscreen could be locked into position. In combat situations, when the driver’s vision hatch was locked in the closed position for protection, an episcope was swung into position. Another means of vision to the front when the hatch was closed was for the driver to peer through the vision slit in the armored hatch. It was 5 inches (12.7) wide by 3/16 of an inch (4.76 mm) tall. Bulletproof glass, which was normally stored underneath the driver’s legs, could be quickly placed behind the vision slit. A small periscope gave limited vision to the right side of the tank, but the driver could not see to the left. He had to rely on the tank commander and the hull machine gunner sitting on his left to see that everything was clear.
The two steering tillers, when drawn back, engaged an epicyclic gear by clutch withdrawal and brake application to the plant ring. By pressing a knob on the end of the handle, an alternative brake could be applied which operated on the spider, thereby locking the track. Thus, the driver could steer by either epicyclic or clutch and brake methods. Communication between the driver and the commander was by a system of colored lights.
The Hull Gunner’s Position
The hull gunner was seated in a similar seat to the driver on the left side of the tank. He was also the radio operator and had to act as the co-driver. His position was rather cramped due to the wireless sets being placed on a level with his left shoulder. The machine gun on his right was fitted in a ball mounting. It had a limited traverse to the left and right due to the height of the sprocket wheels and mudguards. The gunner’s telescope was rather dark and had neither brow pad or eye padding. This would cause injury if used on the move. The ammunition belt of a hundred rounds was fed into the feed block and the remainder of the belt was suspended on guides from the roof, the whole belt being fed out of the ammunition box. The machine gun could be clamped in a central position and fired by the driver, who had a remote control trigger on his nearside steering tiller. The hull gunner sighted the gun through an open site visible through his periscope. The sight was a metal rod about 12 inches tall with a ring on the end. The base of the rod was attached to the glacis plate in front of the driver’s position.
The radio had two alternative aerials, one being a 10-foot vertical rod giving a range of 5 km, and the other being a ‘battle’ aerial carried on the running board and giving a range of 1 km.
The Czechoslovakian built Praga TNH-P 8-ton tank was armed with a Skoda 3.7 cm L/48.7 gun and two 7.92 mm Zbrojovka Brno vz.37 machine guns (MEE)
Turret Gunner
The turret gunner, who was also the tank commander, had a canvas sling seat. He was provided with a nonrotating cupola which had three small periscopes and an episcope mounted on its four sides. He was assisted by a loader who operated the coaxial machine gun. The examination team commented on the report, “The optical apparatus, though ingenious, does not give as good vision as the War Department equivalent.” The 37 mm main gun and coaxial machine gun could be fired singularly or both together. The main gun mounting could be either elevated by shoulder control or by a gear control, the firing trigger being on the handle of the latter. When the gun was being fired, the mounting was locked in the position adopted and could not be elevated or depressed so long as the gun was firing. The turret could either be rotated by a hand traversing gear or by free traversing. Locks were provided for both the turret and the gun mountings for traveling. There was no internal turret basket. Ninety rounds of 37 mm shells were carried in boxes of 6 rounds. Usually, 30 of these rounds would have been armor-piercing, and the remaining 60 would have been high explosive shells. Each armor-piercing shell weighed approximately 2 lbs. The high explosive shell weighed 1.8 lbs. There was stowage for 2,700 machine gun rounds carried in 100 bullet belts, 3 belts fit in each ammunition box. Nine hundred of the rounds were armor-piercing.
This photograph of the side view of the Czechoslovakian built Praga TNH-P 8-ton tank was taken in England (MEE)
The Hull
The British examiners looked at the tank’s fire precautions and the means of exit available to the crew in an emergency. The tank had two main crew hatches, one through the cupola lid in the turret and another above the hull gunner’s head. “Both are adequate,” was their conclusion. It was noted that the driver did not have his own exit hatch but had to either get out through the turret hatch or, if that was blocked, clambered over to the hull gunner’s position and got out through his hatch. It was also recorded that it was possible to get into the engine compartment through a small door in the offside internal bulkhead and to open the louvers from inside and get out that way. A large fire extinguisher was conveniently mounted on the wall of the fighting compartment.
The Czechoslovakian built Praga TNH-P 8-ton tank’s Praga TNHPS/II 4-stroke, 6-cylinder in-line 125 hp petrol/gasoline engine was at the rear of the tank. (MEE)
The Engine
The tank was powered by a Praga TNHPS/II 4-stroke, 6-cylinder in-line 125 hp engine. A hand crank could be used to start the engine from inside the tank as well as from outside the vehicle. A mechanical governor limited the engine speed to 2,000 rpm. The maximum speed of 42 km/h (26 mph) was based on an engine speed of 2,200 rpm. Therefore, the top speed at the governed 2,000 rpm was only 38 km/h (23.6 mph). The engine was cooled by water circulated by a pump driven off the timing gear.
The radiator was mounted at the rear of the engine. Air was drawn in through the louvers under the engine covers, one on each side. It could also be drawn from the fighting compartment by opening slots in the bulkhead. The air inlet to the fighting compartment was controlled by opening an adjustable flap over the brakes and two small louvers. “It was not considered adequate. Steering gear pollutes the air with hot Ferodo and oil fumes,” the inspectors remarked. Air was drawn through the radiator by a ‘Keith’ type exhauster and out through a bullet-proof louver facing upwards on the rear of the tank. This exhauster was coupled to the crankshaft through a universal joint. There was a slipping clutch incorporated in the fan hub. The system did not contain any pressure valves. The vehicle exhaust was very quiet and, on cross-country work, the whole vehicle was quite unlike some other tanks, but it was very noisy on roads due to track noise.
No engine oil cooler was fitted, but the large cylindrical body of the oil cooler was finned and afforded some cooling properties. A large oil bath filter was used for filtering the engine air. A large “Autoclean” filter was fitted in the lubricating system of the engine. This also incorporated the relief valve for oil pressure. All petrol and oil pipes were of a flexible rubber and canvas hose type, secured by clips. The petrol tanks were in the engine compartment, one on each side. They held 24 gallons each. Petrol was drawn from the tanks by an A.C. engine operated pump. An electric “Autopulse” pump was also fitted for emergency use.
Transmission
The transmission was through a single plate clutch in the flywheel. This could not be withdrawn, however, as its only purpose was to give a ‘slip’ if the Wilson gearbox engaged too fiercely. The power was then transmitted by a propeller shaft through the fighting compartment to a Wilson five-speed and reverse box situated between the hull gunner and driver. This box was kept cool by taking the oil to a cooler incorporated in the radiator. There was also an ‘Autoclean’ filter situated in the radiator. Bolted onto the gearbox was the bevel box, which transmitted power to two epicyclic steering assemblies. These consisted of the normal clutch, epicyclic gear with brakes on the planet ring and spider. In addition to the two bands required for steering, each assembly had a third band that operated on the spider drum and was used for breaking. The power then passes through a final reduction to the sprocket, which was mounted on the front of the vehicle. The transmission was accessible for maintenance. The brakes could be adjusted either from inside the hull or through the flap, which admitted cooling air to the steering assemblies. This flap had four positions controllable by the driver. Only one was bullet-proof. This allowed the flap to be opened a quarter of an inch (6.35 mm), in which position a flange on the outside prevented the entry of bullets.
Suspension
The suspension consisted of two assemblies on each side that carried the hull on knife edges. Each assembly had two wheels. The wheels were 31 inches (78.74 cm) in diameter and were rubber-tyred. The assembly consisted of a leaf spring mounted on the center member and joined to the top of each wheel axle casting. From the center member, there were also two radius arms that ran to the bottoms of the wheel axle casting. The front and rear arms on each side were dampened by a spring-loaded, unadjustable friction shock absorber mounted on the pin joining the arm to the center member. Lubrication was by ‘nipples’ situated in the hubcap of the sprocket, idler and each wheel. The oil was carried by drillings to all necessary parts. The knife edges are not lubricated. The track lay on the two rear wheels but was carried on two small guide rollers above the front wheels.
Tracks
The tracks consisted of manganese nickel steel castings. The track pins were headless and made from nickel chromium or manganese nickel steels. They were secured by circlips. The pin was beveled at each end and had a groove turned in it at the appropriate place. The bevel expanded the circlet, which sprung into place when the groove of the pin reached it. Track adjustment was by adjusting the idler wheel mounted at the rear of the tank. The idler wheel bracket was rotated by means of a worm and ratchet operated from outside the vehicle. It was remarked in the report that the tracks were not new when received but did not appear to have worn much. Their rate of wear appeared low. They were strong and stayed on well.
Accessories
A headlamp, two side lamps, and a tail lamp were fitted. The side lamps had a red glass pointing upwards which could be easily seen from the air. Interior lamps were provided where necessary. A signaling lamp employing three colored lights was issued with the vehicle. There was a small flap provided in the turret top to push it through. A horn was fitted that could only be used when opened up as the wiring was carried through the open sight aperture of the hull gun and had to be disconnected when in action. A mirror in a tin case to protect it from stones was fitted. The electrical system was fully suppressed to prevent wireless interference. The vehicle was fitted with four Ramshorn towing hooks in addition to the drawbar at the rear.
Trials
This tank underwent tests from 17th – 29th March 1939. The weight of the vehicle fully loaded was 9.4 tons (8.52 tonnes). It completed 188 miles (302.5 km) by road and 103 miles (165.7 km) cross-country. The examiners made the following comments:
The commander’s field of view was not ideal. The vision from the episcope and the three periscopes was not continuous. It was also extremely hard to judge distance through these instruments. The commander was also hampered when looking through his scopes owing to there being no brow pad.
The hull gunner’s field of view was adequate to cover the ground over which he could fire. The driver’s vision was adequate except for road driving in traffic, as the driver needed one member of the crew to be observing on the outside of the vehicle. The driver’s position was comfortable except that there was not enough headroom. The hull gunner’s position was rendered uncomfortable by the wireless set, causing him to lean continuously to one side. He also suffered from a lack of headroom. The commander’s position was satisfactory, with the exception that the sling seat provided did not allow him to adopt a comfortable position behind the gun. The vehicle, when closed down, did not appear to be adequately ventilated, and fumes given off by the steering gear were very unpleasant after a time.
The power of manoeuvre was adequate and did not vary whether opened up or closed down. The vehicle was also easy to handle on side slopes. The steering required a little skill, as the action of the epicyclic break bands was rapid. Unless the brake was applied skilfully, the tank would turn more than was required when driving on roads. The controls were well-placed. The vehicle did not skid under normal conditions and was safe at any speed it could attain. It did not suffer from reverse steering, but when descending hills, the steering became very insensitive and heavy. The vehicle was not very large and was as conspicuous as a light tank. The balance of the turret was difficult to estimate, as it was extremely awkward to traverse under any circumstances. The traversing handle was very badly placed by British standards. It was to be operated while looking out of the cupola and not while looking through the telescope.
The suspension of the vehicle rendered it unsuitable as a gunnery platform. It had a short sharp juddering motion of about two inches pitch which rendered it impossible to keep the eye to the telescope. Apart from this, it was quite well sprung and rode across country about similar to the Tank, Cruiser, A9, Mk.1. On roads, the suspension was at times affected by a juddering motion, but otherwise, it was satisfactory. The capacity of negotiating natural obstacles was not adequate for a cruiser tank. It could cross a 5-foot stream but failed to cross a 6-foot stream due to the back falling in as the bank gave way. It would not climb a 4-foot sandbank; the sprocket failed to pull the nose up. It could be fitted with seven spuds on each side of the vehicle’s tracks. These spuds were quickly attached to the track, but the short length of the vehicle did not enable it safely to climb more than 3-foot vertical obstacles. It was estimated that the vehicle could cross a 7 foot hard sided trench. The vehicle climbed a 2 foot 10 inches wooden vertical obstacle. This was the safe maximum owing to the angle to which the vehicle tipped itself.
The tank was driven continuously for 94 miles on roads. It took 4 hours 35 minutes and the average speed was 20.5 mph. The average fuel consumption was 3.13 mpg. Fuel consumption over cross-country courses was 2.1 mpg. After a total of 291 miles, the oil levels did not need topping up. Life of the brakes appeared satisfactory. On a 188 mile journey to Lulworth Ranges, they did not require adjustment. They were only adjusted once after about 260 miles. Two engine stoppages occurred after the vehicle was being tested due to the changing from one fuel tank to the other. No special filters seemed to have been fitted. The tank underwent a number of tilting tests and performed satisfactorily.
Final Observations of the Mechanisation Board dated 22.5.1939
“The attempt to produce an inconspicuous machine with observation arrangements immune from bullet attack has resulted in a cramped fighting machine with control inferior to our standards. The “dance” of the vehicle … is particularly marked on roads and is due to the combination of long pitch narrow bar tread tracks and un-dampened suspension.”
Conclusion
The British rejected purchasing the Praga TNH-P 8-ton tank because it was deemed inferior to the current British Cruiser tanks, such as…, in its ability to cross obstacles, lack of smooth ride, and cramped fighting compartment. It was too thinly armored to be considered an infantry tank. Its Skoda 37 mm gun was not as powerful as the British 2 pdr gun. The tank was returned to the factory. In May 1940, the British fought in France with their Cruiser tanks against Panzer 38(t)s employed by the Germans. The Panzer 38(t) and its derivatives would stay in service far longer and in far higher numbers than any of the initial British Cruiser tanks.
The Praga TNH-P 8-ton Tank as tested in the United Kingdom in 1938. Illustrated by David Bocquelet
Specifications
Dimensions (L/W/H)
4.6m x 2.12m x 2.4 m (15ft 1in x 6ft 11in x 7ft 10in)
Total weight
9.4 tonnes
Crew
4 (Commander/Loader, Gunner, Radio Operator/hull machine gunner and Driver)
Propulsion
Praga TNHPS/II 4-stroke, 6-cylinder in-line 125 hp petrol/gasoline engine.
Top Road Speed
42 km/h (26 mph)
Range (road)
250 km (155 miles)
Armament
Skoda 3.7 cm L/48.7 gun
Secondary Armament
2x 7.92 mm Zbrojovka Brno vz.37 machine guns
Turret Armor
front 25 mm, sides and rear 15 mm and top 10 mm
Hull Armor
front 25 mm, sides 15 mm, rear 15 mm and the top and bottom 8 mm
Source
Experimental Report on 8-ton Tank (Praga – TNH-P) MEE Report No.A99
National Archives at Kew WO 194/22.
S. J. Zaloga, Panzer 38(t), Osprey Publishing.
T.L. Jentz and H.L. Doyle (2007) Panzer Tracts No.18 Panzerkampfwagen 38 (t) Ausf. A to G und S.
United Kingdom (1940)
Land Battleship and Leaping Tank – None Built
The United Kingdom declared war on Germany following its invasion of Poland in September 1939. When it did so, there was a sudden realization among many that the country was in yet another major war in Europe against the same enemy they had fought just a generation beforehand. That previous war had been seared into the collective psyche of the nation as one characterized by almost unimaginable and unrelenting slaughter in the mud and trenches of the Western Front – a situation summed up too simply (but commonly) as one ended by the appearance of a new weapon known as the tank.
Faced with a new war, many in Britain foresaw a war fought along similar lines and one which would need new heavy tanks to smash through the German defensive lines, like the Siegfried Line. An official program had started in late 1939 under the auspices of the Special Vehicle Development Committee (S.V.D.C.), but this was by no means the end of ideas. Many inventive and scientific minds would also consider this and other problems associated with the war to come in this uneasy period from September 1939 and the start of the German campaign in the West in May 1940. Known as the ‘Phoney War’, it provided a brief window into the thinking behind some of these ideas for a war which had yet to start in earnest for Britain.
“Too much thought is being given to armies and man-power. This war will be won by the engineer and the scientist”
—Dr. Arthur Janser quoted 23rd April 1940.
Arthur Janser
The man behind this 500-ton tank idea was Arthur Magnus John Janser. Janser is somewhat enigmatic and, although he is known to have come from Austria (with a date of birth recorded many years later in England as 17th June 1903), the chain of events which led to him being in Britain in 1940 are less than clear. An expert chemist, Janser, or ‘Dr. Janser’, as he is often referred to, thankfully submitted several patents in his lifetime, which provide some insight into his life pre-1940. Janser submitted his first patent in 1925 in Vienna (Austria) followed by another at the same time in Berlin-Charlottenburg, Germany. By 1934, he was in Paris, and by 1936, he was in London.
“Mr. Janser is a monarchist…being Viennese, [he] gave us some great inside dope on how the Nazis were confining his friend Sigmund Freud, the great psychologist”
—Memoirs of William ‘Bill’ Temple (2013).
He is described at times as an Austrian refugee and this is likely correct given the Anschluss ended Austria as an independent state in March 1938. By 1936, however, living in London, he managed to become engaged with a group of amateur (but by no means amateurish) scientists known as the British Interplanetary Society (B.I.S.). Formed in Liverpool in 1933, the B.I.S. expanded to London in 1936.
The British Interplanetary Society
Janser’s knowledge and skills as a chemist were much needed by the B.I.S., where he would propose solid rocket fuel motors for their various space rocket ideas. Other members of the B.I.S. included:
Arthur C. Clarke (astronomer and noted science fiction author post-war),
D. W. F. Mayer, H. Bramhill (draughtsman),
Jack Happian Edwards (Head of the Technical Committee and Director of an Electronics firm),
Ralph A. Smith (artist and engineer – his son later worked on the Apollo programme),
Maurice K. Hanson (mathematician and payload specialist),
William F. Temple,
S. Klementaski (biologist),
H. E. Ross (electrical engineer and man behind Project Megaroc in 1946 to adapt a German V-2 into a pilot carrying rocket),
J. H. Edwards (research director),
Eric Burgess (a writer, founder of the B.I.S., and a NASA consultant after the war),
H. E. Turner (editor of the Manchester Interplanetary Society magazine), and
A. Val Cleaver (aircraft engineer and Chief Engineer for Rolls-Royce rocket division).
Some of the meetings of this group were even held in Janser’s flat.
“A middle aged foreigner, Mr. Janser, a research chemist (who said he’d made a lifetime study of atoms) was smiling to himself most of the time, occasionally making dry comments, superiorly on his pinnacle of knowledge of the slow, lengthy, laborious & patient research necessary even to project a rocket into the stratosphere”
—Diary entry of William ‘Bill’ Temple, 10th November 1936.Photograph of B.I.S. members at the inaugural meeting in 1936 in London. Professor A. M. Low is in the center at the front. Janser is in the back. A red dot has been placed above him to identify him in this photograph.
Source: Burgess
Janser, along with several other members of the BIS, were also a keen followers of Science Fiction literature (including Arthur C. Clarke), attending a convention held in London April 1938 on the subject of space travel. Janser did not attend the 1939 convention, although Clarke did, perhaps indicating that Janser was less interested in science-fiction stories than he was in the science-realities behind them.
“Mr. Janser is a many-sided genius. He has a bookcase which covers an entire wall, and it is full of books on every aperture of science, from chemistry to psychology, from astronomy to Biology”</blockquote>—Memoirs of William ‘Bill’ Temple (2013).
Janser’s primary contribution to the B.I.S. was his proposal for solid propellant arranged in a cellular manner to produce enough thrust to propel a rocket to the moon. To this end, according to H. E. Ross, Janser produced between 80 and 120 possible propellant combinations for rocket fuels.
Members of the British Interplanetary Society meeting in London (probably at the B.I.S. convention) in 1938.
Left to right: J. H. Edwards, Eric Burgess, H. E. Turner, Midshipman C. Truax (USN), R.A. Smith, M. K. Hanson, and Arthur C. Clark.
Source: National Air and Space Museum
Although the B.I.S. members, consisting of about a dozen scientific experts, were not the first to consider rockets or space travel, they were the first to do so in such a systematic and thoughtful way. The Technical Committee of the B.I.S. considered each and every aspect of what it might take to put a man into space one step at a time, 30 years before the Apollo missions.
“Item Two of the agenda: the composition of a very light but efficient battery to heat the space-ship. Here Messrs. Edward and Janser started an argument on such a highly technical plane that I just sat there between them, agape, and the stream of words passing over my head like a beautiful rainbow. I gathered it was something about conductivity values. Arthur Clarke made occasional interjections which might or might not have been to the point, but at any rate showed us that Arthur grasped what was going on… It all ended with Mr. Janser promising to hunt through his books (all 2,000 of them) to find certain tables, and perhaps consult the National Physical Laboratory on this important subject…”
—Memoirs of Bill Temple (2013) recounting a meeting of the B.I.S. Technical Committee before the war in Janser’s flat.
Between them, they were a group of men covering a wide range of scientific abilities, and Janser, amongst them, was clearly considered to be one of the luminaries of the group’s most technical elements – rocket propulsion. Just before the war, this team had finished their design for a solid-fuel type rocket capable of reaching and landing on the moon.
The 1938 B.I.S. Moonship and lander – the culmination of the pre-WW2 work by the B.I.S.
Source: British Interplanetary Society
With the declaration of war in September 1939, the society was disbanded shortly afterwards, for the duration of the conflict. Many of those in the BIS ended up in uniform during the war. Janser, as an Austrian citizen, did not. Born in 1903 (his marriage certificate says 1904), he would have been in his late 30s at the outbreak of war and, at this time, many foreign nationals were detained for national security reasons. Many were shipped off to the Isle of Man, and, later, after security vetting, returned to their lives in Britain.
Barricading the Sky
It was whilst working with the B.I.S. that Janser would also meet with famous inventor Grindell Matthews (another member) to provide advice on rocket fuel. Matthews was working on his anti-aircraft rockets which carried a small explosive charge and which pulled a wire behind them to ensnare and destroy enemy aircraft.
Matthews appears to have been inspired by a speech by Sir Kingsley Wood (the Secretary of State for the Air) who had called for an inventor who could devise a way of “mining the skies” as protection against enemy aircraft. Janser wrote about these ideas in November 1939 with the title of “Barricading the Skies”. In the article, Janser discussed several ideas which had been put forth, including a barrage balloon filled with explosive gasses and tethered with electrified cables, electrified clouds, special clouds made from artificial poison gasses to choke the engines of aircraft, and even an all-metal airship replete with artillery.
“Mr. Janser comes around… [for a ‘jabber’]… He indicates that he is working on a new sort of ‘death ray’ & Grindell Matthews is also aiding and abetting him”
—Diary entry of William ‘Bill’ Temple, 22nd October 1939.
It would be Matthews’ rockets which, along with the standard barrage balloons, provided the answer to Wood’s question of protection of the sky. Matthew’s rockets, assisted by Janser’s rocket knowledge, would go on to see service during the war as ‘Parachute and Cable’ devices, bringing Janser’s ‘Barricade in the Sky’ article to reality.
The PAC rocket was a simple and effective anti-aircraft device.
Source: Secret Projects Forum
“Janser told me [Bill Temple] it’s possible we may get a grant of £200 to help Grindell Matthews with his ‘Defence’ research work. Janser said the German military men already had an explsoive rocket which could be fired about 5 or 6 kilometres with more accuracy than a shell & were developing it rapidly. I said we may expect them one day to be coming over the channel”
—Diary entry of William ‘Bill’ Temple, 4th May 1937.
Other Activities
In April 1939, Janser was elected as a fellow of the Royal Society of Arts in London, which allowed him to put ‘F.R.A.S.’ (Fellow of the Royal Society of Arts) after his name. His biography in the Journal of the British Interplanetary Society also shows him with F.C.S., and F.C.I.S. after his name, although it is unclear exactly to what these refer. However, F.C.S. is likely for a Fellow of the Chemical Society (the forerunner to the Royal Society of Chemistry) and F.C.I.S. may be in relation to being a Fellow of the Chartered Institute of Secretaries.
By November 1939, Janser is known to have been living at 28 Great Ormond Street, London from his patent, but he is also recorded with an address in Holburn as well (today, this address is opposite the world famous Great Ormond Street Children’s Hospital).
Other Arms
It is in consideration of Janser’s background, his genius, and his abilities, as well as his writings, such as those in newspapers in this period, that his tank concept makes sense. Janser would write a series of guides for the common person to help them to understand the inventions and ideas being bandied around in relation to the war, such as Matthews’ Death Ray. These appeared in ‘Guide and Ideas’ published weekly as a light hearted edition, with such articles as the secret life of showgirls and then, with Janser, some serious articles as well.
In this light and with war having broken out, he would find himself as an Austrian, an alien from a hostile country clearly trying to not only solve a technical problem, but also show his loyalty to the UK. Many such aliens were taken away, interned for reasons of national security and then progressively released. Janser appears to have been caught up in this and was interned on 25th April 1940. Interestingly, his internment ceased on 16th October 1940, and he was exempt from further internment. This was presumably because he was working for H.M. Arsenal in Woolwich at the time and they needed his expertise, but also marks the softening of the hard-line approach by Winston Churchill, which had previously ordered all foreign nationals detained as a possible security risk.
His tank concept was not lengthy or perhaps not particularly well considered. It did, however, reflect much of the concerns of the time about a war stuck between the French Maginot Line and the German Siegfried Line.
The Enormous Tank
In spring 1940, Janser was to write and espouse the need to rethink the trend of small and lightly armored tanks. Something much bigger, much stronger, more powerful, and much better protected than ever before was going to be needed. He declared that “recent advances in metallurgical research” allowed for the construction of tanks not just bigger than those in service, but bigger than those which had ever been in service before or since.
To make use of this knowledge, Janser suggested a tank of up to 500 tons could be built, protected by armor as thick as that on a battleship (30 cm or more) “mounting siege guns which fire special concrete breaking shells”. Assuming for a moment that advances in metallurgy were really such that new armor could be more powerful, then this would be a level of protection technically beyond that of a battleship. What he called “double-strength” steel was to be used and made with minerals unavailable in Germany. This new armor would effectively render it indestructible to enemy fire and unmatched on the battlefield.
What it really represented, was a totally unnecessary level of protection to guard against any possible threat from enemy guns. It was also a preposterous statement indicative either of someone trying to make a point merely about the level of protection (that of an indestructible vehicle), or simply that he did not have a clue what he was talking about in terms of armored vehicles, or maybe a bit of both.
He was, in spring 1940, simply repeating the same sort of thoughts and concerns of some in the upper echelons of the British military, in terms of thinking of bigger tanks to smash the Siegfried Line and specifically the concrete bunkers along it. What he did, however, was to go beyond ever their wildest fever-induced dreams of giant tanks. Janser produced a vision of a vehicle gliding over enemy tank traps and defensive works with impunity:
“A tank of five hundred tons built of this double-strength steel would sail serenely over tank traps and be impervious to land-mines. Ferro-concrete booby traps would crumple under its advancing caterpillars”
He may well have been correct in assessing that a tank of such weight might, simply by virtue of its great weight, crush beneath its tracks the sort of reinforced concrete structures arrayed before it in defensive lines. What he missed, however, is that the same weight of machine would undoubtedly perform the same task on the way to the front itself, destroying its own sides’ bridges, roads, and railways as it went.
Nonetheless, this 500-ton tank idea was certainly the right ‘scale’ of number to garner press coverage as far afield as Australia.
“Dr. Arthur Janser, famous Austrian research chemist now a refugee in England, believed that the Siegfried Line can be smashed. But new weapons and new types of ammunition are wanted..”
When Janser, in spring 1940, mentioned the need for new weapons and ammunition to fight the war, he was, of course, correct. The ‘500-ton’ tank may simply have served as a literary device to get attention to his call and he continued the description of his idea to reinforce the point.
Not only was this monstrous machine to be ludicrously heavy (more than two and a half times the weight of the heaviest tank ever made – the German Maus), but also armed with a siege gun. The standard British siege guns of the era were the BL 60-pounder (5 inch) and BL 9.2” howitzer. Both of these guns dated to WW1 or before and could fire large high-explosive shells weighing 27 and 130 kg out to a range of more than 9 km. Certainly, both guns would provide a phenomenal amount of firepower for such a tank and, given an overall weight of 500-tons, the size and weight of the guns became a moot point. Janser, to enhance the power of the siege guns, also proposed new and special anti-concrete shells which could thus shatter the German ferro-concrete bunkers, dragon’s teeth, and barriers of the Siegfried Line.
Janser did not elaborate further on his 500-ton tank idea but, assuming that 500-tons was a real prospective weight and not just something to engage the reader in consideration of new larger tanks, then it would need an engine. The largest tank built in Britain during the war was in the region of 80 tons and powered by a 600 hp engine, delivering around 7.5 hp/ton. Assuming an equivalent power to weight ratio was needed for this machine, Janser would have required engine/s capable of delivering 3,750 hp. This would have been well beyond any road-vehicle of the era and putting it squarely in the territory of power plants from either a ship or a locomotive.
Robot Soldiers
If the 500-ton tank idea was just a bit too much of a step into left field, and a ‘miss’ for the futuristic leanings of Janser, then his second point was spot on, albeit several decades too early.
Following on from this call for a new better armed and armored species of giant tank, Janser also proposed that to beat the Germans, more ‘robot-soldiers’ would be needed. By this, he was referring to his knowledge (from where he did not state) that the Germans and Czechoslovaks had, before the war, “exploited the possibilities of automatic machine-guns and the remote control of guns”.
The modern reader may be a little perplexed as to how a remotely operated gun is conflated with the word ‘robot’. In the 1940s, a ‘robot’ was simply a term being applied to not only a sort of shiny metallic humanoid, but also what today is considered more of a drone or remotely separately weapon of some description. A notable example of this term was the famous V-1 flying bomb being referred to in WW2 as ‘Robot Bombs’.
Any disappointment at the lack of a 1940s-era Cyberman concept, however, is quickly dispelled as Janser describes “robot soldiers armed with machine-guns or grenade-throwing apparatus and controlled by beam radio”, so whether he really thought of mechanical men or just drone vehicles is unclear. The use of drone vehicles is, of course, not a modern phenomenon, but the mass use of drones and unmanned ground combat vehicles is on the rise, albeit 80 years after he mentioned it. Just like then too, the issues of radio control being jammed or intercepted was a concern, and Janser stated:
“Even enemy jamming of the wireless waves could not put the robots out of action”
This rather vague additional line implied at least some level of direct control, so it possible that it was yet another simple rhetorical device to make his readers ponder the problems. Perhaps too, it was an acceptance of the limitations on a fully remote system and a tacit acknowledgement that the robot vehicle would still need a human crew member, with its weapons operating remotely instead. Either way, unfortunately, he chose not to expand on the idea.
The Grasshopper
The final of Janser’s three tank–related concepts was for a grasshopper tank. This was not a tank built to look like a grasshopper, but one which could, conceivably, be used as an alternative to driving-over and crushing obstacles, by simply leaping over them. In this part, Janser chose once more to bemoan the small light tanks in service and felt that some special war machine of this type, might, instead, be able to move quickly from place to place by jumping.
Oddly, for rather ill-considered or technically improbable idea, the Grasshopper idea was a real plan in Australia in 1944, although one unlikely to have been directly inspired by Janser’s call. Not only that, but back in the UK, there were also experiments with the use of rockets to ‘leap’ a vehicle over an obstacle or from the mud in which it had become stuck. No doubt Janser, being a rocket fuel enthusiast, would have approved in general terms of the idea of combining rockets and tanks, although the outcome was less than successful.
Before and after of experiments with a Universal Carrier and rockets – not an optimal outcome.
Source: Pinterest
Conclusion
What can be made from Janser’s work on tanks? Was he really serious about a 500-ton or even a Grasshopper tank? The answer is ‘probably not’. Both such ideas were well within the common frame of science fiction, and, whilst he was not a writer himself, he did attend at least one convention and spent a lot of time with men very much in the sci-fi field and who wrote stories on it. Perhaps their influence rubbed off a little and, combined with the literary technique of what might be closely related to modern ‘clickbait’, Janser grabbed his readers’ attention with a ‘500-ton tank’. For the same reason that a 400-ton tank would be not less equally ridiculous but not hit the same attention-grabbing mark, Janser’s point was nonetheless clear.
Britain had, in general terms in 1939 and 1940, tanks which were in his opinion on the whole too small, too lightly armed, and too lightly armored. In specific terms, even the best of these tanks, the A.12 Matilda, which had a good level of protection, was still utterly unsuitable to lead a charge breaching the Siegfried Line to carry the war into the heart of Germany. Janser was not alone in that view, and various other projects and ideas were espoused at the end of 1939 through into 1940 for similarly large and heavy assault vehicles.
Unlike some of the wacky ideas of random members of the public and the occasional tweed-jacketed home inventor, Janser had a significant level of skill and knowledge in rockets and chemistry. This did not translate directly to tanks, but he continued his work and writing through the end of the war.
On a personal note, despite having applied for naturalization in July/August 1939, Janser was not naturalized until May 1947, at which time he was already married to Thora Ruby Christian Janser. He also became a fellow of the Physical Society in 1947 and had also been elected as a member of the Royal Society of Mechanical Engineers.
He would remain in London and continue his work as a “Research and Consulting Chemist” with an address of 3 Edgeware House, Chapel Street in May 1947, and in 1958, he provided the introduction to a book on past-life regression through hypnosis. Janser died in London in 1964, aged 58. His wife, Thora ‘Ruby’ Christian Raymonde (or Fairbairn), whom he married in Westminster in 1942, survived him and died in 1990.
The B.I.S. would continue its work too and is still going to this day, working on the problems of space travel and life on other planets. The author wishes to express his gratitude to the B.I.S. for their assistance in preparing this article.
—Work of the BIS on Pathe in 1947.
Specifications Janser’s 500-ton tank
Crew
u/k
Dimensions
u/k
Weight
500-tons
Armor
‘battleship’ levels of improved steel
Armament
‘Siege’ guns
Engine
u/k
Speed
u/k
Propulsion
tracks
Sources
Aberdeen Journal, ‘Barricading the skies may be next development’, 23rd November 1939.
Auckland Star, Volume LXXI, Issue 96, 23rd April 1940. ‘Monster Tanks and Robot Troops to smash Siegfried Line: Austrian Chemists’s Plan.
Austrian Patent AT141130, ‘Verfahren zur Herstellung fein verteilter, technische verwendbaraer Pigmente aus Eisenverbidungen’ filed 26th April 1933, granted 15th November 1934.
Bloxham, D. (1958). Who was Ann Ockenden. Neville Spearman Pub.
British Patent GB521718, ‘Shellac modifications’, filed 23rd November 1939, granted 29th May 1940.
Burgess, E. (1993). Outpost on Apollo’s Moon. Columbia University Press, USA.
Cairns Post 29th March 1940 ‘Siegfried Line can be smashed’.
England and Wales Death Registration Index 1837-2007. Volume 5c, Page 1003m.
England and Wales Death Registration Index 1837-2007. Volume 17, Page 82.
England and Wales Marriage Registration Index 1837-2005. 1942, Q2, Vol 1A, P.112: Westminster Street.
French Patent FR771057, ‘Procede de preparation de pigments colores, a base de fer’, filed 23rd June 1933, granted 16th July 1934, published 29th September 1934.
French Patent FR771056, ‘Procede de preparation d’un succedane du linoleum ou de la toile ciree’, filed 23rd June 1933, granted 16th July 1934, published 29th September 1934.
French Patent FR781763, ‘Proceded de fabrication de cartons et de papiers ayant des properties de la nature de la fibre vulcanisee’. Filed 12th February 1934, granted 4th March 1935. Published 22nd May 1935.
German Patent DE454831, ‘Kuntsmasse’, failed 9th April 1925, granted 18th January 1928.
Gippsland Times, 11th April 1940.
Internment record for 547264, Arthur Janser. 1940.
Janser, A. (1939). Fuels and Motors. Journal of the British Interplanetary Society. No. 5.
Journal of the Institute of Mechanical Engineers (1943). Volumes 150-152.
Journal of the Royal Society of Arts, 28th April 1939, Vol. LXXXVII, No. 4510
Kilburn, K. (2007). Eric Burgess: Manchester’s first Rocket Man.
Matthews, G. (1943). The Death Ray Man. Hutchinson and Co., London, UK.
McAleer, N. (1992). Arthur C. Clark. Contemporary Books, USA.
Nelson Evening Mail, Volume LXXIII, 27th May 1940. ‘Monster Tanks and Robot Troops to smash Siegfried Line: Austrian Chemists’s Plan.
Newcastle Journal, ‘What Germany has lost’, 2nd December 1939.
Northern Star 9th April 1940 ‘Siegfried Line can be smashed’.
Pahiatua Herald, Volume XLIX, Issue 14444, 25th May 1940. ‘War of Science says Chemist’.
Parkinson, B., & Scott, A. (2013). The British Interplanetary Society from Imagination to Reality – 80 years. Slideshow.
Proceedings, Physical Society (Great Britain), Vol. 59. (1947).
Queensland Times, 31st January 1940.
Register of Deaths, England.
Reichhardt, T. (1997). Smithsonian Magazine: H.M.S. Moon Rocket
Ross, H. E. (1967). The British Interplanetary Society’s Astronomical Studies 1937-1939. First
Sheffield Daily Telegraph, ‘Barricading the Skies’, 23rd November 1939
Sheffield Daily Telegraph, ‘New Fibre’, 2nd December 1939.
Steps Towards Space: Smithsonian Annals of Flight No. 10. National Air and Space Museum, Smithsonian Institution Press, USA.
Sunday Sun (Newcastle), ‘Truth about Death Ray revealed’, 20th August 1939.
Temple, B. (2017). “>The Archive, The Second Convention (1938).
Timaru Herald Vol. CXLVIII, Issue 21621, 5th April 1940. ‘Siegfried Line – Austrian says it can be smashed.
UK Naturalisation Certification Arthur Janser HO334/176/25305, dated 3rd May 1947.
US Patent 1766817, Substitute for hard paper, ebonite, fiber, and the like and a process for manufacturing the same, filed 24th June 1925, granted 24th June 1930.
US Patent US 2590323, Electrical Apparatus, filed 30th December 1947. Granted 25th March 1952.
Winter, F. (1983). Prelude to the Space Age. National Air and Space Museum, US Government Printing Office, USA.
Western Mail, ‘Winning Prizes from the Pool’, 21st August 1939
Westminster Marriages 1942.
United Kingdom (1934)
Infantry Tank – 1 Prototype Built
Of all the tanks in WW2 which may be derided or even mocked for being ‘ugly’ or useless, one which invariably makes the list is the British A.11 Matilda. This is partially the result of the overall poor showing of the British Expeditionary Force (B.E.F.) in France in 1940 and partially because of the strictures placed upon the design of the vehicle in the first place. It is also because the vehicle is generally not well understood and its combat record unappreciated.
The only people who really appreciated that latter element were the Germans in 1940, for whom the A.11 and its big brother, the A.12, came as a well-armored and unpleasant shock.
Whilst the A.11 was only in service with the British Army for a few years, it left a mark in the form of one of the most successful tanks of the whole war – the A.12 Matilda.
Misunderstood and underappreciated, the A.11 started as a scribble and resulted in a small, heavily armored tank which proved to be a shock to the Germans at the Battle of Arras in France in 1940. There, in conjunction with infantry and its replacement – the A.12 Matilda, the British succeeded in blunting the nose of the German advance. The A.11 Matilda seen in that battle, however, started with a special and slightly different prototype – the A.11E1 (A.11, Experimental model 1), with a history all of its own.
Origins
The A.11 ‘Matilda’ has its origins in the late interwar period, as the British Army was undergoing some head-scratching over not only the shape and dynamics of a future war but also how it would organize itself and what it needed to fight it. The British were generally cautious with new developments in tanks, due in no small part to the trauma of WW1, with the huge losses of men and equipment, and also to the significant limitations on expenditures as the British Empire sought to reconcile the cost of defending Europe from Germany.
Any new development, therefore, had to meet both a developmental limit, the new needs of the Army, and the strict budgetary constraints in force. Luckily for the British, these highly conservative restrictions matched with the equally austere Sir Hugh Ellis, Master General of Ordnance (M.G.O.) and Major-General A. E. Davidson as Director or Mechanisation (D.o.M.). Both men were skilled and competent in their field, with Davidson also a respected engineer, but both still saw future war along the lines of the last one.
In debating the primary role of a new tank for 1934, it was thought that it had to support infantry (an ‘I’ or ‘Infantry’ tank) in the attack against enemy infantry and positions. Enemy tanks could be dealt with by artillery, so a new tank really just needed heavy protection from enemy infantry and anti-tank guns as well as the means to deliver machine-gun fire. As it had to support infantry at their pace, the speed was almost irrelevant. As these two men debated their plans for what a new tank needed to be and how it should work tactically, they consulted with Major-General Percy Hobart, who was Inspector of the Royal Tank Corps (R.T.C.) at the time and proposed two solutions:
A small tank with a crew of two men armed with machine guns built in large numbers to swarm the enemy.
A heavy tank with a cannon.
The solution selected was the first one and, in October 1935, the legend of vehicle design, Sir John Carden, was approached to develop this idea. A skilled engineer and talented vehicle designer, he was also the head of tank design at Messrs. Vickers Armstrong Ltd., meaning whatever he designed, he could get into production quickly.
Sir John Carden, the brains behind the A.11 (Centre) seen on 3rd October 1935 at Heston Airport. Source: Flight Magazine.
His rather crude initial sketch, finished on 3rd October 1935, was for this two-man small tank with a single turret and a single machine gun. A week later, this sketch was taken by Sir John Carden to Colonel M. A. Strudd, the Assistant Director of Mechanisation (A.D.o.M.). Being a technically simple vehicle and with no concerns over getting it into production in the time scale the Army was planning, just 6 months, it was approved as a project under A-vehicle number A.11. One thing not mentioned in most histories of the A.11 is revealed in that original sketch – the crossing of trenches by the vehicle was an important point, which perhaps hints at the sort of warfare terms about which the Army was still thinking. This new tank would manage to cross an impressive 8’ (2.4 m), more than adequate to cross any standard infantry trench.
Sir John Carden’s original sketch of the A.11 shows a low and long vehicle with a small cylindrical turret and, clearly noted in the corner, a protection level of 60 mm. Note the trench crossing width is clearly shown as 8’ (2.4 m). Source: Fletcher
It is commonly repeated online and even in some books that the ‘Matilda’ name was selected after the prototype was seen ‘waddling’ like a duck. The connection between Matilda and Duck is unclear in itself in this false history especially, as that particular Disney character with that name only appeared after the war. The name could, of course, not have been penned after seeing it move, as it is first written down on 10th October 1935, when the tank was not much more than a doodle. In fact, ‘Matilda’ was just a company name for the project – a code word to disguise what the vehicle was, although officially it remained just ‘A.11’.
The price of the project, at a time of small defence budgets, however, was somewhat extraordinary, some £15,000 for all of the development and draughting costs. In 2020 values, this is over £1m and each tank was projected to run at £5,000 (£364,000 in 2020 values). For a tank armed only with a small machine gun, this was still very expensive. This is a vehicle often referred to as cheap being built to a budget. For sure, it had a budget to be built to, but it was by no means a miserly one. For reference, a small light, machine gun (or even cannon-armed) tank from the same firm, like the Vickers Light Patrol tank, was on sale in 1933 for just £700 (around £51,000 in 2020 values). It is hard, therefore, to square quite why this Infantry tank might justify costing more than 7 times what that tank would.
Vickers Light Patrol Tank seen in 1932. The same prospective armament at 14% of the cost of an A.11. Source: Beamish CollectionVickers 6-ton Mark A tank. The general lines and shape of this tank show a clear line of thought carried across to the A.11. Source: The Tank Museum, Bovington
Armor
Armor for this new type of tank was going to need to be heavy – very heavy for the era which given that even 20 – 30 mm or so was considered good protection for many tanks is saying quite a bit. A standard thickness of 60 mm was proposed for the tank, with the plate made from Vibrac 45 armor steel produced by the (Vickers) English Steel Corporation. The roof and floor plates were eventually to be just 10 mm thick and made from Homogenous Hard tank armor and proof against .303 rifle fire. Originally, however, for the prototype, the hull was not going to be made from armor plating, but mild steel ‘soft plate’ instead. On A.11E1, the rear and hull roof were made using thinner plates than that used on the eventual production models, just 7 mm thick for the floor and roof and 8 mm thick at the rear – albeit heavily sloped.
This is common enough in a prototype tank, as it makes manufacturing easier and cheaper and permits modifications to be done quickly prior to production. Of note too is that this prototype was only made in plate 60 mm thick, as this thickness was considered sufficient protection against the primary prospective enemy anti-tank weapon of the time – the excellent German 37 mm gun (3.7 cm Pak 36).
Factory fresh German 37 mm anti-tank guns. Source: Rheinmetall
Despite having the appearance of a tank riveted to a frame, like many other tanks constructed in this period, the structure was physically strong and stiff enough that it was, in fact, simply riveted together without a frame.
Prototype – A.11E1
Despite being a technically simple vehicle, this first vehicle, A.11E1, now with an official War Department index number of T.1724, was not finished until September 1936, when it was handed over to the Mechanisation Experimental Establishment (M.E.E.).
A.11E1 seen shortly after delivery in September 1936. Of note are the lack of exterior fittings on the hull, such as lights and stowage boxes, with the exception of a cranked tubular tool mounted on the front half of the left side, parallel with the track. This photo shows to a good level of details of the original rubber-tyred return rollers and the toothed idler wheel at the front. Source: Beamish Collection
Firstly, on 9th December 1936, splash tests were conducted at Farnborough and the turret, in particular, was found to be a problem. Here, under concentrated machine-gun fire using standard ball ammunition, it was found that the mantlet could actually break up under the stress of multiple impact and allow splash to enter the vehicle, to the detriment of the crew. As a result of this, Messrs Vickers-Armstrong replaced the mantlet with a cast steel mantlet which would chip away under the repeated stresses of concentrated fire, but would neither jam nor break up.
Some three months later, on 16th March 1937, armor plating 60 mm thick of the type intended for the primary armor was tested at Shoeburyness. Here, it was found that, whilst 60 mm rolled plate and 60 mm castings were sufficient to stop armor-piercing shots from the British two-pounder, there was not sufficient additional protection to allow for a sufficient margin of safety. As a result, the armor was recommended to be upgraded to a new requirement 65 mm thick with a tensile strength of 75 tons (76.2 tonnes) for production vehicles.
Further splash trials were carried out in November 1938 and, once more, there were problems. Specifically, splash could enter through the large driver’s hatch as well as through the engine louvers. On top of this problem, the bullet-proof glass selected by Vickers had the unpleasant characteristic of splintering when shot and had to be replaced. Quite why this testing process had to be dragged out over a nearly two-year period when the whole tank was needed ‘within 6 months’ is somewhat unfathomable. Nonetheless, the lessons from the trials meant that modifications to both thickness and splash protection were made between A.11E1 and production A.11 models.
Most noticeable are the changes around the driver’s area. On the prototype vehicle, the sidewalls of the hull are straight and cut flush with the surface. This created a sharp edge and provided no angling to reduce splash from small arms, which could go towards the driver’s hatch. These top edges of the side were therefore chamfered at roughly a 45-degree angle. Likewise, the tendency for splash to penetrate the leading lip of the large hatch was rectified with a protective strip riveted to the top edge of the driver’s panel. An additional change was the addition of a pair of horizontal raised strips across the full width of the glacis. These ribs would stop rounds that struck the glacis from ricochetting up into the direction of the driver’s visor or hatch edge. One splash guard which was later to be modified from the A.11E1 design, however, was the one that ran across the width of the hull roof in front of the turret. By the time the vehicle entered production, this was not as high and just covered the bottom edge of the turret.
Comparing the hull front around the driver’s area from A.11E1 (left) to a production A.11 (right) highlights the findings from the splash trials. The chamfering of the vertical side armor is obvious, as is the splash guard on the driver’s plate. Noteworthy too are the horizontal splash guards across the glacis plate to further reduce the problem. Source: IWM
Layout
The vehicle itself was very simple in arrangement. With just two crew, the driver sat centrally in the front, operating the steering and propulsion via levers and pedals. Behind him, and manning the gun as well as commanding the tank, was the second crew member, the commander. Both these men occupied the small yet adequate fighting compartment and were separated from the engine by an internal bulkhead. The driver sat forward in the hull and was provided with a single, full hull width rectangular hatch above him. This large hatch was supported by two hydraulic cylinders due to its weight. No episcope was originally fitted to A.11E1., but this was added during testing. Without it, the driver was limited to just a narrow view directly ahead when the hatch was closed – with it, he could provide additional situational awareness to the sides.
The rear of the vehicle sloped sharply downwards over the engine bay. Perhaps the most distinctive feature of the A.11 was the lack of mudguards over the top of the track run. This is surprising given how simple such a guard would be, whether in metal or even canvas (like the Medium Mark A ‘Whippet’ from WW1). The lack of a mudguard meant dirt and branches could be caught up in the tracks and dragged along the side of the tank or thrown up onto the engine deck, none of which would improve either the mechanical or combat efficiency of the tank. The only effort to prevent such a situation were rather small and sturdy guards fitted only over the rear-drive sprocket, which was a feature of the production vehicle – another lesson from A.11E1.
Left side view of A.11E1 providing an excellent study of the suspension bogies, with the two pairs of wheels on spring leaves connected to a central support with a return roller above and integral to them. Note the toothed front idler has already been replaced and the low position of the front stowage box ahead of the leading bogie. Note that the addition of the stowage boxes has moved the tubular tool to the rear half of the hull. The flattened end of the tool is visible next to the rear sprocket. Source: IWM
Size
Overall dimensions for A.11E1 were very much those of a small tank. Just 15’ 11” (4.85 m) long and 7’ 6” (2.29 m) wide from the outer track edges, with the track centres 6’ (1.83 m) apart. Overall, the top of the turret was barely 6’ (1.83 m) from the ground – an ideal size to cover a man advancing behind the tank. By the time the trials had ended, this increased to 6’ 1.5” (1.87 m) to the top of the episcope on the turret roof. Ground clearance was also very reasonable, measuring some 9.5” (240 mm) from the ground. For the sake of reference, this meant that the A.11 was shorter in length and height, and only slightly wider than the already small Renault FT of WW1.
Oddly, the trench crossing idea of managing to bridge an 8’ (2.4 m) wide trench from the original plan had been abandoned. The final design would manage just 6’ 6” (1.98 m), still enough to cross a normal infantry trench or a small ditch, whilst also keeping the overall length (and thereby, weight) of the machine down. Climbing performance was also acceptable, as those exposed tracks projecting from the front of the tank could easily grip onto a surface to help it climb a parapet or low wall, as long as it was no higher than 2’ 6” (0.76 m) high.
One other consideration in obstacle crossing for the design was the main armament, which, because it did not project, added zero risk of it becoming lodged in the bank of a ditch the tank was entering, as would be an issue with a long-barrelled weapon. That is not to say that the weapon in its armored cowl did not cause obstructions, because it did. It fouled on the driver’s hatch to the extent that, with the gun forward, the driver was not able to have his hatch fully open. No official fording capacity was noted in official data for the A.11.
Fittings
Every tank has to provide some external fittings and items for practical purposes, like lamps, so the vehicle could operate at night, or stowage for crew items externally, in order to free up internal space. The A.11E1 was absolutely no different but was supplied bare. No lamps, no boxes, almost no tools and this would indicate that the intention was to find a location during the trials.
Soon after trials started, these fittings started to appear, with a pair of odd-looking boxed-in headlamps fitted on stubby arms which projected from the sides of the hull, just level with the front of the turret.
The almost bare A.11E1 during trials, showing that the turret roof arrangement had yet to be decided, as it was completely absent, and that no episcope had yet been fitted to the driver’s hatch. The first of many modifications can, however, be determined, with a wing mirror fitted to the front right hand side to assist the driver in seeing behind him and with the pair of boxed-in headlamps on either side. Source: The Tank Museum, Bovington
With the first essential fittings added – those necessary to drive the vehicle safely, then followed the turret roof, with a boxy style of episcope and a rotatable episcope fitted into a hole cut in the front angle of the driver’s hatch. These two additions provided much-needed situational awareness for the crew. As the first suspension changes took place, so too did the stowage on the tank, going from none to two large boxes placed low (so as to not block the driver’s view slit) on either side of the driver’s compartment. The final change or addition during testing was the result of the lack of mudguards. For whatever reason these were left as just small and somewhat flimsy sheet metal covers which only went over the sprockets and no further. By the time the tank would enter production, some additional modifications took place with those lessons learned from A.11E1, like changes to the stowage and headlamps, plus additional features, like smoke grenade launchers on the turret, fire extinguisher mountings, and tow cables, but the essentials of the tank were sound.
The boxed-in headlamps in their protective casing would be changed too – standard car-type headlamps could be used instead. They would be easily damaged by enemy fire or even passage through heavy scrub but they were also cheap, simple, plentiful, and easy to fix.
One non-essential item which was added as almost an afterthought was a mine plough designed by the firm of Fowler. The Fowler coulter plough (coulter is not a company, but a vertical blade in front of the ploughshare itself), as it was called, was a somewhat ungainly device consisting of a pair of long arms formed from steel girders, with one on each side of the tank. Operated up and down from travel position to a deployed position via a drum-driven chain from a power take-off on the back of the transmission, the plough could be lowered so that the wheels on the ends of the arms ran along the ground surface.
A tubular framework projected ahead of the main frame, which ensured the plough followed the terrain ahead and kept scrub from clogging the front of the device. Behind this was a set of coulters on each side, which would cut the ground and ploughshare the dirt and any mines concealed within it to the left and right of the tank’s route. This was first tried on A.11E1 in 1937 and was found to be highly successful, to the extent that the necessary fittings for such a plough were then added to the first production A.11 tank, although, by then, the need to get tanks off the production line was more important than a rather complex device which had never been part of its original purpose.
A.11E1 showing the original Fowler mine-plough in use. Note the absence of the tubular framework on the front. Source: The Tank MuseumThe modified Fowler mine plough, as fitted to the first production A.11. but first trialed on A.11E1. Source: IWMA.11E1 during trials. It can be seen that the episcopes still have not been added to the driver’s hatch or turret roof, but that the toothed front idler has already been removed. Of note is the unusual shelf stowage concept on the upper right of the hull for what appear to be metal ammunition boxes. This does not appear later and appears to have been a failed modification which had been trialled. Source: IWM
Suspension and Tracks
The original sketch from Sir John Carden showed suspension substantially different from the ones which the vehicle was subsequently built with as a prototype. In the provisional sketch, there are clearly 4 distinct and separate bogies, each with a pair of road wheels and with a spring connected to the hull and the rear of each pair. Above each bogie was a track return roller. The system drawn closely matched that of the Dragon Mark IV Artillery Tractor produced by Vickers-Armstrong. It was almost certainly meant to be based upon that system. Just like that system, the tracks used were a medium pitch design made from cast manganese steel and connected together via a single steel pin. Each link also featured no rubber pads for use on roads, but a pronounced spud to gain better traction on soft ground.
However, when the vehicle was produced, it would not use this Dragon or Dragon-like Horstman suspension, but a different Vickers product derived from the suspension of their 6-ton tank.
As a matter of some confusion in the tale of the suspension for these vehicles, there are multiple marks of vehicles and there are several distinct suspension variations worked through on Vickers products at the time.
In essence, however, this proposed suspension consisted of a pair of bogies with a flat arrangement of 4 pairs of road wheels, each mounted in pairs. Each of those pairs was connected to one end of the spring leaves, providing a degree of movement, as the entire bogie could also rotate around a central pivot point. The design was complex. Using small wheels, whilst allowing them to be placed closer together, also resulted in a small external unit that was easily clogged with mud. This style of suspension had already been rejected by the M.E.E. as a problem, so it can only be surmised that it was added as a cost-saving measure, as it was already in production.
A.11E1 seen after modification from its first trials. Source: IWMRear three-quarter view of A.11E1. bearing the vehicle registration mark (VRM) CMM 880. The heavily sloped rear deck is readily apparent. The arrangement of the back was modified to provide additional protection from small arms fire on the production vehicles. Source: IWMProduction A.11 Matilda showing the change in the shape of the armor plating over the rear deck. The relocation of the exhaust from the centre of the rear to the right side is also shown. Photo Credit: Craig Moore
If there is criticism of the A.11, it has to focus mostly on this decision of choosing a system based on an idea from 1929 which the Army already disliked and had proven to be disappointing during testing. This was not a decision likely to find supporters, yet the solution was available and in production and it did work to the extent required. Pragmatism meant the suspension, as fitted, would be kept and that tweaks would have to be made just to make it work.
As it underwent testing at M.E.E., various problems were quickly identified and one of the first was that the toothed front idler was unnecessary. Further, the track was found to be collecting stones and these could become jammed in the rear sprocket. The solution to the former problem was simple – just replace the toothed idler sprocket with a non-toothed one. The latter was resolved in April 1937 and consisted of raising the rear sprocket by 5 inches (127 mm). This would not be the final change to the suspension of the A.11 during its service, but the A.11E1 had set the shape and suspension type which remained with the A.11 throughout its military career.
The hull production had changed too. The original sides of the A.11, as seen on A.11E1, were a simple two-piece fabrication with an offset vertical line of rivets about halfway down the length. On the production vehicles, this seam was retained, but the rearmost panel was now two panels which also had to be riveted together. This added a little weight to the vehicle, but also simplified production by reducing the amount of cutting of the thick armor plating which was required. Rivet-counters will also note that the front of the tank shows a different layout of rivets as well. On A.11E1, the nose of the tank was a separate panel and bolted onto the tank with a column of four bolts on each side. The glacis plate was likewise bolted onto the tank and the nose plate was changed for production. In production, the flat edges of the glacis plate were chamfered and riveted to the structure of the tank. The nose plate was now integral with the extensions either side of the front idlers and all riveted in one piece to the front of the tank.
Radio
No radio was fitted to A.11E1, presumably as a cost and complexity saving measure. Right from the outset, in 1935, no wireless set had been planned for A.11. This would be rectified by the time the tank entered production, as the Wireless Set No.11 was available by 1938 and would eventually be fitted as standard on all production tanks, although this would obviously add weight and take up valuable space inside.
Trials
Other than the already known problems with the suspension system chosen, the A.11 had a remarkably easy birth when it came to testing. The exhaust pipe being moved was just one of those small changes identified during testing to avoid problems in production vehicles. Indeed, that was the entire purpose of testing and the A.11 can be considered to have tested out very well.
Stowage
The two large stowage bins fitted to A.11E1 were varied for production models but remained essentially the same – two large boxes, either side of the hull. On the A.12 vehicle, which followed the A.11, these stowage bins were moved forwards and downwards to flank the nose of the tank. Behind the curved front armor of the A.12, those front bins actually provide a misleading shape on the front of the A.12, giving it a full-width flush appearance when it is, in fact, a narrow nose-shape just like the A.11. Moving those boxes forwards in that manner and making them integral with the vehicle also provided the advantage of some additional protection for the A.12.
Engine
Power for the A.11E1 was provided by a 3.62 litre Ford V8 petrol engine delivering 70 hp connected to a Fordson four-speed crash (manual clutch) gearbox. Drive for the 11.5” (292.1 mm) wide manganese steel tracks was delivered from this gearbox via final drives at the rear, connected to the sprockets. Steering was provided through a system of clutch and brake steering (i.e. brake the right track to turn right and vice versa), which was taken directly from the Vickers light tank and controlled by the driver in the same manner – a pair of steering levers. One problem identified during testing was that the exhaust pipe from the engine was prone to cause the engine oil to heat up, so it had to be rerouted, but this was a simple affair and certainly not a failure – just a tweak to avoid a problem. It meant a very minor external change of the exhaust from the rear deck at the bottom in the middle to the right-hand side of the back instead.
Cramped is one word – an efficient use of space however, might be another explanation for the very tight fit of the 3.62 litre Ford V8 70 hp engine in the bay. The incredible thickness of the armor can be seen on the left on the top of the exposed side plate. Note that the cable seen at the top is a hatch release for the engine deck connected to the catch at the top left of the photo – it could only be released from inside the tank. Source: Fletcher
The engine was small and the result was a relatively slow vehicle. However, this did not matter. Indeed the A.11E1 proved to be faster than expected and perfectly satisfactory for speed. From the notes of Col. Strudd at that 10th October 1935 meeting with Sir John Carden when the tank concept was presented, it is clear that the Army was perfectly satisfied with a top speed of just 5 mph (8.0 km/h) although 8 mph (12.9 km/h) would be better. The A.11E1., could, in fact, achieve a top speed of 10.9 mph (17.5 km/h) on a road and 5.8 mph (9.3 km/h) off-road, but this was not a problem at all for the design, as it only had to keep pace with infantry on foot. The average speed the tank could sustain on a road was 8.17 mph (13.1 km/h) and 5.6 mph (9.0 km/h) off-road.
The internal fuel tanks held 43 Imperial gallons (195.5 liters) of petrol for an official maximum operational range of 80 miles (129 km). With 43 litres of petrol and a known fuel consumption rate during the trials of 2 gallons (9.1 litres) per hour on-road and 1.8 gallons (8.2 litres) per hour off-road, that also meant up to 21.5 hours of road use and 23.8 hours off-road.
Turret
Made in a single piece, the turret was a substantial casting with armor 60 mm thick all round. Provision was made for a single armament – either a Vickers .303 caliber machine gun or the somewhat beefier .50 Vickers instead.
Almost cylindrical in shape, the basic elements of the A.11 turret were the same as drawn originally by Sir John Carden. The cylinder was angled at the back, providing a little more space, and the front carried forwards the trunnions for the main gun, all within this one-piece casting.
Atop the turret was a simple circular hatch which opened in 2 pieces – two quarter circles at the rear half, forming a semicircle, opened out and the whole front half of the turret roof formed the other semi-circle. On the left side of this front half-circular hatch was the single episcope for the commander.
Turret roof of T.3347 showing the unusual split hatch. Source: Chris Stillito, Armour in Focus
The original turret casting for A.11E1 was a little more complex than on the production model. The outer edge on the front half of the turret at the top is the reference point for spotting the difference. On the prototype, there is a pronounced half-rim running around the front of the turret and projecting from the sides. This is not easily visible on the production turret, which replaced this hard rim with a more rounded and less pronounced outswell, although the purpose was the same – to reduce the chances of ricochets up the sides of the turret hitting an exposed commander. The turret was also asymmetrical, with that rear swell offset to the right at the back and the front casting for the armament offset to the right as well at the front. This meant that the trunnion mount can be seen on the right-hand side of the turret but not on the left and the reason for this offset is obvious – it allows the commander to share space with the gun. With the primary (and only) weapon on the A.11 being the single machine gun, it was belt-fed from the left, so setting the gun off slightly to the right allowed the commander to operate the gun and reload it much more easily.
The rear of the turret would noticeably change from A.11E1 too, from a rounded back on the prototype to the production turret which angled-off the swell at the back of the turret and created a short ‘step’ underneath – a very modest change to create a little extra space inside.
The rear of the A.11E1 turret (above) differs noticeably in shape from the rear of the production turret (below)
Two more small features of note on the turret which would change from A.11E1 would be the addition of a small triangular bracket for mounting a radio antenna base on the rear right-hand side for the No. 11 Wireless Set inside, and the addition of a pair of mounts for the smoke grenade launchers, one on each side of the turret and operated by cable from inside. Both the addition of a radio and smoke grenades would be substantial improvements from the very basic tank which was A.11E1.
Armament
A.11E1 was intended to support infantry by providing not just a mobile protective shield in front of them, but also to suppress enemy positions with machine-gun fire. The machine gun, not the cannon, was the primary choice for killing enemy troops and destroying machine-gun positions, which were a major threat to the infantry. For A.11E1, the original weapon chosen was simply the standard water-cooled .303 calibre Vickers machine gun albeit, with a short note which followed saying “we can try our idea of M/C gun but this is not so urgent”.
‘M/C’ in this context may be taken to mean ‘Machine Cannon’ i.e. a heavy machine gun with added anti-armor capability over the standard .303 machine gun or another compact gun capable of firing a small high explosive charges as well. The details were clearly not finished, as the priority was to get the tank into development as soon as possible. The small turret would make the fitting of a larger gun harder but not impossible. For the development of the A.11, just two guns were selected, either a .303 calibre Vickers machine gun or its heavier brother, the 0.5 calibre Vickers machine gun. Whatever ‘machine cannon’ Sir John Carden and Colonel Strudd were discussing in October 1935 is not known.
Vickers .303 calibre Mark IVA machine gun. Source: The Vickers Machine GunVickers 0.50 calibre Mark V heavy machine gun Source: The Vickers Machine Gun
Armament Options for A.11
Gun
Vickers Mark IVA
Vickers Mark V
Caliber
.303
0.50*
Muzzle Velocity
744 m/s
760 m/s
Weight (vehicle mounted)
65 ½ lbs. (29.7 kg)
71 ¾ lbs. (32.5 kg)
Rate of fire
500
650-700
Belt size
250 rounds
100 rounds
Note
* 12.7 x 81 mm (.5 Vickers also known as the ‘.5V/580’) rather than the 12.7 x 120mm (0.5 Vickers High Velocity also known as the ‘.5 V/690’). The number after the ‘V’ in both cases referred to the weight of the bullet in grains rather than a velocity
Both types of machine gun were available with a variety of ammunition, from a lead core ‘normal’ bullet suitable for general use to an armor-piercing round. When it comes to the common complaint about the A.11, that it was under-armed, the existence of armor-piercing ammunition for both guns has to be taken into consideration.
For the .303 caliber gun, armor-piercing rounds had been available since WW1, as had incendiary rounds. The Mark.VII.W.z Armour Piercing round of 1917 (known later as the W Mk.Iz from 1927) was a 174 grain (11.28 gram) cupro-nickel jacketed bullet with a 93 grain (6.02 gram) steel tip. Traveling at 762 m/s, the bullet was designed to meet a requirement that 70% of rounds could penetrate a 10 mm thick armor plate at 100 yards (91.4 m). An effective anti-armor range of 100 m does not sound like much, but was perfectly adequate to deal with close-by enemy positions and also for suppressing protected targets further away.
For the 0.5 calibre gun, the armor-piercing round was known as the ‘Armour Piercing W. Mark 1z’ and also featured a hardened steel core. The penetrative requirements for this round were that 7 times out of 10, it would be able to penetrate 18 mm of armor plate at 0 degrees and 15 mm at 20 degrees vertical, all at 100 yards (91.4 m). A tracer version of this round, known as the SAP Tracer FG, came in various marks and there was even an incendiary version of it, known as the ‘Incendiary B Mark I.z’.
Whilst the .303 was an ideal weapon for suppressing enemy positions, mowing down enemy troops and dealing with soft-skinned vehicles, it was not suitable for picking off enemy forces behind a shield, like a gun crew. It was also not suitable for dealing with light enemy armor. The option of mounting the .50 calibre version removed that problem at short ranges. Both guns were perfectly adequate for general work, with acceptable accuracy on target out to at least 1,500 m. Both versions were virtually indistinguishable from each other when fitted into the turret and concealed within the large cast armor housing over the water-cooling jacket, although only troop leader’s tanks were fitted with the 0.50 calibre.
Some 3,000 rounds (12 belts) of .303 caliber ammunition were eventually to be carried as standard, which would be sufficient for just 6 minutes of continuous automatic fire. In the trial photos, there is one which appears to show half a dozen ammunition cans on a shelf on the right hand side. Assuming this was an attempt to carry more ammunition, then that would be several more belts for perhaps as much as 5,000 rounds carried. Boxes for the .50 Vickers ammunition held just a single 100 round belt, such was the greater size of the round. Assuming the ammunition stowage for both guns was to be proportional, this would mean 1,200 .50 Vickers rounds, enough for just 2 minutes of continuous fire.
Production
A contract for the production of 60 tanks was signed at the end of April 1938 and, ten days later, another order for the same amount came, meaning a total of 120 tanks. This would be enough to provide tanks for 2 whole battalions.
Conclusion
The A.11E1 was a successful prototype. It arrived late and perhaps this was partially the result of the untimely death of its creator, Sir John Carden, in December 1935 in an air crash. Certainly, there was nothing particularly novel about the tank or some new technology that had to be invented for it to exist.
The A.11E1 occupies an unusual space within British tank design too, as it languished in that period in the 1930’s where a new weapon was needed, but not one was entirely sure on what they were really going to need. Nonetheless, the design was still capable of being modified from its original form into something a little more than that and of being a capable platform for a device like the Fowler mine plough. The reality for it was that, by the time it was in production and being delivered, there was already a replacement in the pipeline in the form of the A.12 Matilda. That particular vehicle had a much more difficult birth and yet it could not have existed in its final form without the A.11 beforehand. The heavily armored infantry tank which started with A.11 and its prototype A.11E1, became the foundation of the heavily armored A.12 and its most dominant feature. The A.11E1 should, therefore, not be seen as some retrograde step for the Army to some attempt to rerun the First World War, but an attempt to learn from that war and produce a tank sufficiently protected for the next one.
The first production A.11 off the production line. In this head on view, the offset of the machine gun to one side is evident, as is the very narrow profile the tank presents front-on to an enemy. Source: FletcherMatilda A.11E1. Illustration by Stoneheartisk.Top view of the Matilda A.11E1. Illustration by Stoneheartisk.Rear view of the Matilda A.11E1. Illustration by Stoneheartisk.Right side view of the Matilda A.11E1. Illustration by Stoneheartisk.Front view of the Matilda A.11E1. Illustration by Stoneheartisk.
Specifications A.11E1
Dimensions (L-H-W)
15’11” (4.85 m) Long, 7’ 6” (2.29 m) wide, 6’ 1.5” (1.87 m) high
Engine
3.63 litre Ford V8 petrol producing 70 hp
Speed
top speed 10.9 mph (17.5 km/h) on road and 5.8 mph (9.3 km/h) off road, cruising speed 8.17 mph (13.1 km/h) and 5.6 mph (9.0 km/h) off road.
Side view of the TOG Citadel with the shortened 60 pounder gun. Illustration by Ed Jackson, the winner of our illustration competition.
United Kingdom (1939)
Heavy Tank – Concept Only
Background
The battlefields of the Western Front during WW1 were characterized by thick belts of barbed wire covered by machine-gun fire often from concrete bunkers, creating an area which was all but impassable to infantry. The ground, shattered by years of war and millions of rounds of artillery fire, was often a quagmire of mud into which men, beasts, and machines would drown. Even if they managed to cross all of that, they would be faced with having to cross enemy trenches, anti-tank ditches, minefields, and other obstacles.
The British tanks of WW1 were specifically designed to overcome much of these problems, adopting a characteristic quasi-rhomboidal shape in which the tracks would run over the top of the hull, producing a high leading point for the track and carefully shaped to maximize the ability to both climb a step and cross ditches.
The early designs were relatively crude affairs, with inadequate armor, quickly falling prey to German anti-tank rifles and slow enough to be hit by enemy artillery. As the war progressed, the British progressively improved the armor and layout to the pinnacle of the whole design evolution, in the form of the Anglo-American Mk.VIII heavy tank. It had improved armor, improved mobility, in a larger tank with more firepower, and still retained the ability to extract itself from the terrible ground conditions. However, that tank did not get the opportunity to show its true power during the war and the mass production of it, which was being put in place, was canceled with the end of the war. Nonetheless, the principles had been established and if only thinking in WW1 terms, then this layout of the tank was clearly going to be ideal.
In 1939, many people could see the clouds of war gathering over Europe as an expansionist Nazi Germany under Adolf Hitler became more and more assertive, dominant, and militaristic. With the 1938 invasion of Czechoslovakia by Germany, any doubts about the future aspirations of Hitler to become the preeminent military power in Europe were over. Despite the appeasement of men such as the British Prime Minister, Neville Chamberlain, Germany was not going to cease in its growth and there was little time to prepare for a new major land war.
Thus, on the eve of war, and apparently with little comprehension that the nature of this forthcoming conflict was going to be different from those conditions experienced 20 years prior, the Army was in a rush to find a heavy tank. They simply resorted to exactly what they knew had worked before, a Mk.VIII shaped vehicle, albeit with more armor and firepower than before and the additional task of smashing reinforced bunkers.
It is not without a substantial degree of irony that the man substantially responsible for the Mk.VIII design, Sir Albert Stern, had, unlike the Army, moved on in thought. Along with his colleagues on the not yet named design committee, he was proposing a much more modern design in the form of the 300G. That tank featured a high leading track to help climb, a longer hull to help cross obstacles, and firepower concentrated in the turret to better deliver its firepower.
The Anglo-American Mk.VIII tank. Source: Beamish Collection
Origins
Lt. Col. Sir Albert Stern, a man who was very much ‘made’ by his experiences in helping to shape armored warfare in WW1, was in a powerful position, with a title, wealth, experience, and contacts in government. He also foresaw what he thought was to come and, in June 1939, was asked to visit the Minister of Supply, Mr. Leslie Burgin, to discuss the issue of heavy tanks.
The outlook was dire. British tank development had, since the end of WW1, stood almost stationary. There were few tanks, and what there was a mixed bag of various types and quality, with the best armored of the bunch being the A.11 and A.12 Matildas. Both carried substantial armor for the time, 60 mm or more, enough to protect from most infantry weapons available short of artillery, yet both were under-armed and not long enough to perform the sort of assault role envisaged by some British military planners.
Despite the protestations of men such as General Sir Maurice Taylor, Senior Military Advisor to the Ministry of Supply, who was dead-set against heavy tanks, Stern had gathered supporters in the form of men such as Sir Maurice Grove Taylor and Major General Alexander Elliot Davidson, Director of Mechanisation at the Ministry of Supply, to his side.
If there was to be a new and heavy tank, these men decided it should be along the lines of what was already proven and with which they were familiar. Given the parlous state of interwar British tank design and the utter lack of a viable alternative, the outcome was as obvious as it was inevitable, the new heavy tank should be along the lines of the Mk.VIII tank of WW1. Whilst Stern and his team gathered together their expertise and came up with their idea in the form of 300G, the Army would busy itself with its own ideas and generate a list of specifications identified as RBM-17. Then, they made their own outline of a tank to meet their own specifications – the Citadel.
RBM-17
With the 300G in hand, Sir Albert Stern had an outline for what he and the members of his as yet unofficial committee felt would meet the sort of need they saw coming. This was not a full-scale reversion to the conditions of WW1, but an improved vehicle with more trench and obstacle crossing ability than existed before.
The philosophy of a new special tank was therefore already tacitly in place and set roughly even before war was declared on 3rd September. At that point, Britain was suddenly at war with a major and aggressive European power and had no heavy tanks at all. Although this initial idea that a new tank was needed was already in place, it is inextricable that it still took until 29th September for the results to travel all the way from the General Staff to the Adelphi Hotel, where rooms had been prepared for Stern and his team to work.
On 28th September 1939, however, when the Army brought with them their list of requirements for a new tank, it immediately meant that the 300G design, on which the team had been working, was redundant. The Army was absolutely insistent that the vehicle had to have certain features, including the firepower concentrated in sponsons and a large gun in the front to smash bunkers, two features impossible to accommodate into 300G. Further, they wanted a fundamental shift in design from a turreted machine back to an ‘all-round’ track machine, as this would facilitate heavy unditching equipment.
Copy of R.B.M.-17, the original specifications for what the Army demanded from the nascent S.V.D.C. Source: Author’s collection.
The specifications themselves clearly show exactly what the Army felt it needed in terms of a short-range special-purpose tank, but they also show the naivety on engineering matters and of tank design in general, especially as at one point, some felt this could be achieved for a vehicle under 40 tonnes in weight.
Criteria Set
Design
The tank to meet the requirements of RBM-17 was going to have to meet a set of criteria like no other tank had ever been asked to fulfill. This set, in September 1939, may well have seemed impossible to achieve to the General Staff. If one were to assume that they had deliberately set Sir Albert an impossible task to keep him busy and quiet, they were to find that even these extreme criteria were met and exceeded.
Requirement one, and the most important, was that it had to be able to cross a 16’ (4.9 m) wide trench and climb a parapet or other obstacle 7’ (2.1 m high). This was basically the widest anti-tank ditch and a high wall. Both of these obstacles were uncrossable by any British tank then in existence and the RBM-17 was to cross these without the aid of a fascine (a large bundle of sticks to fill in a ditch) or bridge.
Length Requirements
This first criterion, right from the start, guaranteed more than any other that the final size of the machine would have to be at least twice the length of the trench simply to avoid falling into it. A 16’ (4.9 m) wide trench, therefore, meant a tank 32’ (9.8 m) or so long. To climb a 7’ (2.1 m) step meant a very high track at the front in order to get purchase (grip) high on the wall or parapet. It is no surprise that these match the general ‘all-over’ track shape of the Mk.VIII tank.
Shape Requirements
The other reasons the RBM-17 was to follow the Mk.VIII’s shape were equally practical. The tank needed the maximum bearing surface on the ground, meaning the widest track possible, so it would not get stuck in soft ground. It also had to carry heavy unditching gear. In other words, it had to be able to get itself out of a hole or soft ground using a method like that used in WW1, a large spar of timber carried over the top of the tank, on which the tracks could get purchase to pull itself out. This ‘log extraction’ is still in use today and the carriage of an unditching beam or log is now most famously associated with Russian/Soviet tanks, which are often still seen with a log on the back. The method of use is identical in principle except that, in the RBM-17’s case, no crew would need to get out. In order for that spar to be carried over the tank by the tracks and underneath, it also determined that an ‘all-round’ track machine and one without a turret, which would get in the way of the spar, was needed.
Armor Requirements
The tank would have to be immune to both 37 mm and 47 mm anti-tank fire at 100 yards (91 m) and against the impact of a German 105 mm howitzer shell at normal impact. Given that the ‘rival’ A.20 was being considered around a 60 mm basis at this time due to a similar need to be immune to the 37 mm gun and yet could not meet the demand, the RBM-17 would have had to have not less than this thickness of armor at any point. More armor, of course, meant more weight.
The preeminent 37 mm anti-tank gun of the era was the German Pak 36, which could achieve around 64 mm of anti-armor performance at 100 m. For a 47 mm gun, weapons such as the French 47 mm SA 37 could deliver an anti-armor performance up to around 90 mm at just over 500 m and around 100 mm at 100 m.
A 105 mm shell, such as that from the German 10.5 cm leFH 18, was nearly 15 kg in weight with nearly 2 kg of explosives inside. Bearing in mind the often wafer-thin armor on the roof of tanks, being hit directly by such a shell would be devastating. Even a close ‘hit’ landing and bursting nearby was perfectly capable of crippling a vehicle, stripping off wheels or tracks or topping it over.
The Army was demanding immunity at 100 yards (just under 100 m), so clearly anything less than 80 mm of armor was going to be unacceptable, although the attention to protection from artillery would wane a little in emphasis as time went on.
Firepower Requirements
The gun was still not yet decided but had to be in the front and capable of defeating the heavy German bunkers (7’/2.1 m thick concrete) which were so worrisome to the General Staff. As such a gun would, by its very nature, be restricted to only a limited range of fire to the front, the tank would also need side armament to rake German positions as it passed them. Here, the General Staff wanted something simple, just a 2 pdr. and Besa machine gun combination in a sponson on each side. On top of this was to be a separate Besa pointing forwards and another to the rear. Eight smoke dischargers completed the required armament, as these would provide cover for the tank and infantry to follow.
All of this equipment and armament meant a crew complement of 7 to 8 men. The tank was to be powered by a diesel engine to reduce fire risk, fitted with a No.9 radio to speak with other tanks and troops, had to be able to go 50 miles (161 km) on its own and, on top of this, be able to be transportable by rail with little or no disassembly.
It must also be considered that Sir Albert and the soon-to-be-named ‘Old Gang’ clearly thought little of the ‘no turret’ and all-over track idea. Their first design was, in fact, far more similar in shape to the A.12 and A.20 than the Mk.VIII. When the requirements for the length of trench to be crossed were decided, the design grew longer, and when the turret was abandoned and all-round track selected by the General Staff, the Mk.VIII shape was inevitable. Those other TOG designs are known only by drawing number 300G in both a long and ‘compact’ form. Both were shelved in favor of the Mk.VIII approach, although the longer version would later be resurrected when a modicum of sanity returned to the General Staff.
In these early days, the selection of armament was a key consideration and a variety of armament and mounting options were considered across Sir Albert’s work and the A.20, including a 2 pdr./Besa 7.92 mm machine gun combination, as found in the turret of the A.12 Matilda, a 3” howitzer, a 3.7” howitzer, naval 6 pounder, and the French 75 mm gun, as used on the Char B1.
The 2 pdr./Besa option would only work if a turret was going to be selected for the tank, which meant a hull-mounted gun. With the 3” and 3.7” guns being low-velocity weapons, they were abandoned. This was because the work of Sir Albert had been given a very strict and very specific set of requirements, one of which would require a particularly powerful gun firing a high-velocity shell capable of breaching 7’ (2.1 m) of reinforced (ferro) concrete.
The requirements were specifically listed under the heading “Super-Heavy Tank (Land Battleship)” under the code ‘RBM-17’. The exact meaning of those code letters has never been adequately explained but, given that Sir Albert’s committee was already being labeled in a sort of British public-school humor kind of way as ‘The Old Gang’, it could be speculated that such a boyish kind of name was being thought of here for this ‘Really Big Machine’. The committee designing this vehicle would later (October 1939) receive a formal acknowledgment as the Special Vehicle Development Committee (S.V.D.C.), but they were equally happy using the ‘TOG’ term themselves as a badge of honor rather than as a mark of scorn, as has been happily assumed by some authors in the decades since the war.
The Citadel Design
Brigadier Kenchington from the War Office and Colonel Watson were the men who brought the RBM-17 specification ‘wish-list’ to the meeting with Sir Albert Stern. With them too was an interpretation of what this would look like for the committee to work on. It is not clear if the vehicle outline that they brought with them as a ‘Citadel’ tank was directly from these individual officers themselves or from the War Office or General Staff or a mix of the bunch, but the design was clear in realizing the needs of RBM-17.
The outline for the Citadel, labeled as ‘TOG-1’, dating somewhere between September and probably November 1939. Source: The Tank Museum, Bovington
Layout
The presented vehicle was a long, low, lozenge-shaped tank, roughly along the lines of the Mk.VIII, but with a large field gun mounted in the front of the hull with heavy unditching gear. It was drawn showing large round, presumably cast sponsons for the 2 pdr. / coaxial machine gun combination. One important note on this design is the issue of crew access. No doors are shown and, in correspondence over the next month or so, the only comment on this topic was on the removal of side doors behind the sponsons. This too was presumably similar in intent to the Mk.VIII, although the shape or style of such a door is unlikely to have been the same given the heavy armor requirement.
Side access doors for the WW1 era Mk.VIII were thick enough to protect against small arms and even anti-tank rifle fire, but were nowhere near the armor required by RBM-17. Likewise, the idea of a door-mounted machine gun was never contemplated, as the side machine gun was to be coaxial with the sponson-mounted 2 pdr. Note the small rails for the unditching beam on the back do not extend forwards to the casemate. Source: US National Archives
On top of the tank and projecting above the level of the tracks was a raised superstructure with a small cupola. This lookout allowed the commander to see where he was going and communicate to the driver in the front left. Whilst it may or may not have been rotatable, it was not an armed turret. The more notable issue on this raised section in the fighting chamber was that, just like the Mk.VIII, it would prevent the whole unditching beam over the top of the tank idea as well. Here, then, there seems to have been a disconnect in the minds of the military planners for the General Staff, who seemed to be confusing the earlier marks of British tanks, which used rails over a small raised structure for an unditching beam to travel over, with the rear-mounted beam on the Mk.VIII. Photographs of the Mk.VIII clearly show that the rails on its roof only extended over the rear section of the tail and thus that the beam would then not be able to be carried forward to help unditch the vehicle. The Mk.VIII therefore would only be able to deploy this beam backward to reverse out of a particularly boggy hole, whereas the early tanks, such as the Mk.IV, could deploy the beam forwards to get out of a hole forwards or in reverse.
Shown post-war on display, this vehicle clearly shows the issue of the top rails, whereby a beam or other equipment, such as a fascine could be dragged over the top without fouling on the casemate. Source: Pinterest
Armor
No details on the armor for the Citadel idea were noted, other than the immunity requirement. Given that 37 mm and 47 mm anti-tank guns could respectively perforate between around 60 and 80 mm of armor at 100 yards (91 m), the requirements guaranteed armor not less than that already in use of the A.12 Matilda, with 3” (76 mm) of armor. Importantly, the immunity requirement did not specify that the armor had to be that thick per se, just that it needed to provide that level of protection. Whilst the vertical sides would need to be at least that thick, the front may not have needed to be, given the slope, but even so it would seem unlikely that the front, even sloped, would be thinner. The same is true of the sponsons, with their distinctive curved shape, projecting from the sides. Given the size of them, each would likely weigh roughly the same as the turret of the A.12 as well. It is not hard, therefore, to see why the desire to replace two of them with just one turret would finally win out later.
Armament
RBM-17 made it clear that the Army wanted a field gun in the front which could breach enemy heavy bunkers up to 7’ (2.1 m) thick and various options would be discussed with the S.V.D.C. as they tried to meet this demand. Of the options considered, there was little to choose from.
The biggest gun which could potentially be made to fit in the front was the venerable 60 pounder. The B.L. 60 pounder was over 30 years old and had seen extensive service in WW1, firing a 60 lb. (27 kg) shell containing 8 lbs. (3.6 kg) of high explosive at 650 m/s out to a range of 9 km. The gun itself was massive, employing a wheeled carriage and usually serviced by a crew of 10 men when used as a field gun. Even so, it produced a rate of fire of just 2 rounds per minute. The gun was also very long, with the barrel alone measuring nearly 5 m from breech to muzzle. This produced a problem for the front of the vehicle, as the barrel would potentially impale itself into an obstacle, such as the opposite face of a ditch when the vehicle was crossing it. Thus, the option of shortening the barrel was considered, even though this would reduce the muzzle velocity of the gun. However, as the long version firing HE could not defeat the 7’ (2.1 m) of concrete, the Army demanded that the gun would not be shortened.
Little discussion seems to have focussed on the two other huge problems of using such a gun in the front. Firstly, the fact that just one man was supposed to operate it and, no matter how much bully beef he might get, this would be an enormous task for one man who was also at some point supposed to use the front machine gun too. The second issue was how to mount such a heavy gun in the hull. Perhaps thankfully, this gun was discounted as a realistic option before any precious design resources were expended on trying to create a mounting that could take both the weight and the recoil.
British B.L. 60 pounder Mk.II in service in the 1930s with the British Army. A crew of 5 men can be seen operating this gun, with other men off-camera. Source: wiki
The reality was that, in September 1939, there was no gun that could be mounted in the front which could achieve that 7’ (2.1 m) requirement. Whilst the demand for concrete destruction would be kept, it would end up as an ‘as much as possible’ requirement going forward through the end of 1939, rather than an absolute figure to be achieved.
Speed
The tank did not need to be fast in any way. There was simply no need. This vehicle would primarily be used for smashing enemy positions. Further, a slower vehicle emphasizing protection would resist the deleterious effect of enemy fire which it would attract, provide a more stable firing platform for firing back, and also clear a path for further tanks and troops to follow.
The low speed was also a reflection of reality. Whilst 5 mph (8 km/h) is certainly not by any means fast, it is surprisingly quick across the sort of terrible terrain which might be encountered in a Flanders-type shattered battlefield, with heavy mud and waterlogged ground. In fact, this speed would not only be faster than its forebears a generation earlier over such ground but also faster than any other tank in such conditions as well.
Crew
RBM-17 called for a commander, a driver, and a separate radio operator. Separating the radio operator from the commander, which was usually his dual job in a British tank, would at least take away one burden from him, but the job of commanding the vehicle was not going to be simplified much, as he would have to now control the crew operating the gun in the front hull and both sponsons. Two men, one for the 2 pdr. and one for the machine gun, would crew the sponsons on each side and just one man was supposed to operate the front hull gun on his own.
This herculean task for the front hull gunner/loader would certainly have been more than a little burdensome if a gun like the 60-pounder was adopted, having to haul the shells on his own, load them, aim the gun and fire, and then repeat. This would have been exhausting and slow work in the confines of the tank with all of the other activities going on, especially if it was moving at the time.
Power
The powerplant for this machine was not mentioned, described, or suggested. The fuel type was clearly spelled out as ‘diesel’. Although high speeds were not called for in the design brief, there was still going to be an issue over the availability of high-power diesel engines and how to transmit that power from the engine/s to the tracks. An eventual solution would be found to meet the need for power from a diesel thanks to Harry Ricardo, the engine designer on the S.V.D.C.
However, in September 1939, it was not that clear cut and engine options were severely limited by not only the power output needed, but also by the fuel type, as few diesel engines were available which could deliver the power of more than 500 hp which would be required and options to be considered included more than one engine, various domestic and foreign engines, and different types of transmissions to maintain efficiency.
An approximation of the Citadel tank of September 1939 modeled from the eventual hull of TOG-1 with the rounded sponsons and shown here with the long-barrelled 60-pdr. gun projecting from the front. Source: AuthorAn approximation of the Citadel tank of September 1939 modeled from the eventual hull of TOG-1 with the rounded sponsons and shown here with the shortened 60-pdr. gun projecting from the front. Source: Author
Conclusion
The Army’s design for the Citadel was odd, harkening back to the worst days of the slaughter of WW1 and no doubt that conflict served up generous helpings of concerns of a repeat of it. Seemingly in haste, the Army had leapt on Stern’s idea that, quite rightly, the Army needed a new special tank to prevent that type of warfare from taking place. Equally, the high command appeared to be panicking. This rush to get ‘something’ is seemingly made clear by the disconnect over the general outline of a tank. The Army were insistent on a turretless tank, so as not to interfere with heavy unditching gear, yet this very requirement was gone even by the end of WW1 with the change from all-over rails to just rails at the back for the unditching beam. Indeed, it is unclear how the High Command seemingly lacked knowledge on the topic, as even in WW1, vehicles had gone away from this type of complete top rail, as seen on the Mk.VIII, Medium Mk.B Whippet, and Medium Mk.C Hornet. Why the Army seemed so insistent on no turret because it would interfere with this equipment makes no sense when a turret would make no more interference than the raised casemate. This, perhaps more than anything else, shows that the Army was rushing to get ‘something’ to fill a need rather than relying on experts like Stern’s committee to develop a new vehicle.
The proposed design had too many crewmen and was too hard to control. Reducing the crew meant fewer men would be needed, more space in the fighting chamber for air to circulate, more space to move around, and more space for storage of ammunition, etcetera. Fewer men could be achieved by the adoption of a turret which would concentrate the firepower equivalent to both sponsons in one place as, afterall, both sponsons could not fire on the same target at the same time in anything other than the very limited circumstances of the target being directly ahead of the tank a distance away.
Removing sponsons would not only eliminate the need for so many crew and improve the interior volume, but would also remove two other significant burdens. One was the problem of transshipment, as no sponsons, or just small machine gun sponsons were far easier to move, fold in, or remove than these huge sponsons demanded. Secondly, their removal would save a lot of unnecessary weight from men, armor, and guns.
Adopting a turret would become the logical conclusion as the S.V.D.C. got to work on the Army’s idea, as saving crew and weight, and improving the distribution of firepower issues altered the general shape of the eventual vehicle into the ‘TOG-1’. Even with a turret, it was not the vehicle that the S.V.D.C. would design to meet the needs of RMB-17. That vehicle would have to wait, as the committee formed under Stern got to work in October 1939.
The size of the machine was inevitably going to be big given the size of the trench that needed to be crossed and the same is true of the front contact, with a 7’ step requiring a high front end. The Army’s demand for an all-road track likewise demanded a machine shaped like the Mk.VIII.
What the struggle to find a suitable powerplant would show was just how unrealistic RBM-17 was as a demand. At one point, the Army’s goal was to make this monster of a tank under 40 tonnes, a completely ludicrous idea that any engineer or designer would have laughed at when the Army was literally demanding a gallon in a pint pot.
In the end, the Army would not be able to get what they wanted. The requirements, although they could be met, could also be improved upon. The S.V.D.C. under Sir Albert Stern would develop a vehicle along the lines wanted by the Army and eventually persuade them of the value of a turret over large sponsons, and that vehicle would be TOG-1. The performance of TOG-1 would also exceed the Army’s requirements for mobility and obstacle crossing and, in fact, exceed their extreme requirements for a vehicle for all but the ability to smash a 7’ thick reinforced concrete structure. That requirement would be practically impossible at the time anyway, regardless of what design they might have come up with, and would remain out of reach for a couple of years until the advent of the 17 pdr.
The Citadel, however, was a starting point for the SVDC, as limited and relatively crude as it was. With a team of experts and mandate for work, the restrictions of RBM-17 would fade a little as the war developed, but the special tank concept would continue and the Citadel became just a footnote in the history of the committee.
Side view of the TOG Citadel with the shortened 60 pounder gun. Illustration by Ed Jackson, the winner of our illustration competition.
The Ansaldo Carro da 9t seen from the side. Illustration by Pavel “Carpaticus” Alexe
Kingdom of Italy/United Kingdom (1929-1937)
Breakthrough Tank – 1 Built
Great Britain was the first nation to deploy tanks in war. The classic ‘quasi-rhomboid’-shaped tanks were first used on the fields of France in 1916. No history of those vehicles is complete without considering the important role of the Lincolnshire-based firm of William Foster and Co. in their design and construction. Other vehicles from William Foster and Co. in WW1 (1914-1919) included the Medium Mark ‘A’ Whippet tank and the Medium Mark ‘C’ Hornet, but by the end of the war, orders for tanks had dried up. There were too many tanks available and not enough need for them, meaning that much of the skills of this firm were languishing unused or were being diverted towards civilian work. Through the interwar period (1919-1939) and especially into the early 1930s, Great Britain was still considered a world leader in tank design and production, with some highly successful designs and exports from the firm of Vickers in particular. William Foster and Co. had no such orders and were, in fact, out of the tank game almost entirely in this period. That is, until the Kingdom of Italy, a nation rearming after the crushing costs of WW1, was researching various designs with which to build a new tank arm to suit its unique needs. The vehicle designed by William Foster and Co. to meet this Italian requirement owed much to its WW1 forebears, a design for an earlier generation of armored warfare.
The need
Despite designing their own tanks in WW1, most famously the FIAT 2000, Italy had, at the end of the war, simply chosen to adopt a French tank, specifically, the Renault FT. The FT was cheap, simple, and available and compared to the large FIAT 2000, far better suited to the narrow roads and small bridges which characterized the north of Italy. More to the point, it was also going to be easier to transport to Africa to settle Italy’s colonial possessions in North Africa, where a faster tank was needed. as it could simply be carried in the back of a truck whereas the FIAT 2000 could not. The FT, therefore, was the logical choice. It was smaller, lighter, and whilst it did not carry the same firepower as the FIAT’s 65 mm gun and several machine guns, it could actually get its small 37 mm cannon or machine guns where they were needed quickly.
Compared to the 40-tonne, 8-man FIAT 2000, the 7-tonne, 2-man Renault FT was a diminutive vehicle. Lightly armed, carrying either a machine gun or a small cannon, and protected by armor up to 22 mm thick, the FT was a good balance of the need to protect the crew inside from enemy small arms fire and weight. With a top speed of 7 km/h, it was meant to be deployed ahead of the infantry to support their advance, suppress the enemy machine gun positions, etc. It was an ideal compromise for an affordable tank with which Italy could arm itself to overcome many of the problems which had plagued it during WW1.
Built under license in Italy as the FIAT 3000, the Renault FT was, despite minor improvements to the original Renault design, adequate but hardly ideal for the future. It was too slow for anything other than static warfare, too poorly armed to contend with heavily protected positions or enemy tanks, and unable to cope with the needs of a post-war military which, by 1923, now included a revolt in its Libyan possession, where a faster tank was needed.
Given the close political relationship between Italy and Great Britain, as demonstrated by its alliance with them and France in WW1, and given Britain’s pre-eminence in tank technology, it is no surprise that serious consideration was given to examining, buying, and adopting British tanks. There was, of course, a serious catch – very little money.
A 1:10 scale model of the Carro da Armato Ansaldo 9t presented to the Italian Army. Note the pair of large headlamps on the bottom corner of the casemate, at the front. This model may still exist in storage at the Military Museum in Rome.
Post-WW1 Italy was still suffering from a serious financial crisis, as it struggled to manage the costs of the war and reassert control over its former colonies. Any tank they chose, therefore, would have to be either built under license or bought outright.
During this evaluation phase for rearming, which started in 1929, vehicles examined and purchased for testing included the Vickers 6-ton tank (Type B), the Carden-Loyd Mk.V*, and the Carden-Loyd Mk.VI. The Vickers 6-ton tank was valuable in terms of size and potential, but was limited by the twin turrets and machine gun armament. The Mk.V* was inadequate for the needs of the Army, generally lacking firepower and protection, but the Mk.VI was more successful. Small and fast, it could meet the needs for a fast light tank which was easily transportable by truck as well as being maneuverable enough to operate in the Alpine region if needed. That vehicle ended up being license-built in Italy and entered service as the CV29 (Carro Veloce – Fast Tank Model 1929), but even this successful vehicle was no panacea to the needs of the Army. It simply lacked the firepower the Army needed to support infantry in an assault role capable of knocking out enemy positions. Vickers was not offering anything suitable and, at some point, the firm of William Foster’s became involved. It is not known whether they reached out to the Italians offering to design something or if the Italians reached out to them requesting a design, but, however, it came to pass, this firm was back in the tank-design game once more.
The original metal model placed over a ‘trench’ to show the capacity for breaching enemy defenses. Note that the model clearly shows a pair of rear-facing ‘machine gun’ positions, with one on each side of the rear of the casemate. Source: Ansaldo
Timeline
The precise timeline of these events is difficult to tie down for a variety of reasons, not least of which being the fact that the two countries ended up at war with each other in 1940 and the British firm was not advertising that it had been aiding what had become a member of the Axis. The other reason for this lack of clarity is on the Italian end. This was a secret program and one which, in 1940, would have come from a foreign enemy power. To this must be added the enormous loss of archival material and records which took place during the war in Italy, especially after the armistice of 1943, the deleterious effects of time on human memory and the conflicting dates for the project.
“In 1929, the company [Ansaldo] decided to send two engineers to Foster & C. Lincoln, Great Britain, in order to design a new tank without a turret. A metal model 1/10 [scale] was presented in Italy … this tank was designated ‘Carro da Armato Ansaldo 9t’, it was armed with a 65 mm gun in the casemate”
The chief draughtsman (designer) for William Foster and Co., William Rigby (one of the key men behind the British T.O.G. designs of WW2), recounted in 1977 (over 40 years later) that:
“In 1937, Foster designed and built a tank for Italy and I went out to the Grand Cornice to test it. It was not a development of the old tanks, it was something quite new, two Italians came over to the works and the whole thing was put under my control. It was used in the Abyssinian war. Me and my daughter went out to Venice just before this and I took an order for a 2’ 6” [0.76 m] threshing machine for Italy, they are usually 4’ 6” [1.38 m]. Then the Abyssinian war started and we were told that if we didn’t get out soon we’d not be able to, so we left quick.”
The Italian invasion of Abyssinia (modern-day Ethiopia) started in spring 1935, which suggests that, as the project for this vehicle started in 1929, it was still undergoing tests in Italy up to around January to February 1935, at least with Mr. Rigby having some involvement or oversight of the project.
Actual construction or assembly, in whole or part, likely took place at the Ansaldo factory in Italy, with construction finished in 1932. It was called ‘Carro armato da 12 tonnellate mod. 32’ (12-tonne tank model 1932) in a 1933 preliminary manual. Unveiled and accepted for trials under the designation ‘Carro armato, 9t’ (9-tonne tank), trials would begin under the direction of Centro di Studi della Motorizazione (English: Centre for the Study of Motorisation)(C.S.M.) in December 1934.
The William Foster design was dominated by a large frontal casemate for the main gun. Note that the casemate narrows at the front to the same width as the hull in this drawing. Source: Pignato
Tests
The vehicle had been built and unveiled in 1932. The first tests of this vehicle, designated Carro da 9t M.33 (9-tonne tank Model 1933), were carried out under the supervision of the C.S.M. through December 1934. During trials, however, the vehicle was found to be unsatisfactory. The top speed was just 22.5 km/h, 3 times faster than the FIAT 3000, but still substantially slower than the CV29 and CV33 light tanks, which could manage 40 km/h.
Modifications were therefore demanded in order to increase the speed and improvements were made in the form of a new engine. In order to improve the ride, a new sprung suspension system was fitted as well in 1935. With the new suspension in place, the older side armor plates were modified to make them smaller. This would offset some of the weight gain from the new heavier engine, although it is noteworthy that a partial side armor plate remained running from the section around the front wheel and extended to about halfway back on the tank. It was bolted to the top of the original frame which held the track support rollers.
According to the account of Mr. Rigby, some of this modification work may have been taking place under his supervision or assistance until the Spring of 1935, but this cannot be substantiated from Italian records at this time. Either way, the modification process was slow and it was not until 1935 to 1937 that the work was completed and the vehicle sent back to C.S.M. for a new evaluation. By 1937 then, some 8 years or so had passed from concept to design and testing, and the needs of the Army had rapidly changed during this period. The most obvious difference to the new design from the Carro da 9t was the suspension, but this was not the first or only modification. The first major change to the design was not the tracks nor the suspension, for the old system had still worked. Instead, this change was to the casemate. The original casemate had been narrow and much squarer, forming a tight box in which the men would fight.
When the tank was reworked, the upper front plate was replaced by a new plate, wider at the top, moving from a rectangle to a trapezoid. Two additional sections of armor in a triangular shape were added to the outside of the front of the casemate, so that the sides could remain vertical. These triangles formed an angular connection from the front to the sides. This change substantially widened the fighting space inside the vehicle and produced a more pronounced overhang over the tracks, as well as a wider appearance from the front. The 3 original vertical bolt lines up this upper plate had 7 bolts each. Whilst the number of bolts in each line was the same on the new wider front casemate plate, a fourth vertical column of bolts was added on the front plate, on the far right. This was because the cradle on the inside of the plate which held the gimbal mount for the main gun was bolted in vertical lines. On the original (rectangular) front casemate plate, the right-hand side of this support frame shared bolts through the frame to create the connection with the side casemate plate. When the casemate was widened, the gimbal support frame remained in the same place, but a new row of holes had to be made for where the frame and casemate side plate would attach. The wider fighting compartment, however, ensured that there was now more space in which to operate the main gun. It would also improve the coverage around the front of the vehicle from the machine guns.
The original front aspect of the design, with three vertical columns of bolts. When the rectangular front of the casemate was replaced with a trapezoidal plate, widening the fighting chamber, it necessitated a fourth line of bolts. Source: Ansaldo with amendments by the author
With the upper front plate of the casemate widened, it also meant replacing the roof plates to fit the new dimensions and also adding in a pair of triangular plates on each side at the front.
In this image, the new wider casemate is clearly visible along with the original closed-in suspension although the wheels already appear to be different from the original blueprint. Note that, whilst only two men are in the image, there is clearly the back of a third seat directly behind the driver’s position. Source: Ceva and Curami.
Pictured undergoing trials after the casemate had been widened, the original suspension is still in place, showing that amongst the faults of the design was not just fightability, but also mobility. Source: Pinterest
The Carro da 9t moves along what appears to be a rocky stream bed during off-road trials at Sciarborasca. The new casemate is in place but the original suspension remains. Source: Ceva and Curami.Climbing the steep rocky bank onto the road, the Carro da 9t has the widened casemate but retains the old suspension. Note the stowage box fitted within the large mudchute. The photo was probably taken during evaluations at Sciarborasca. Source: The Tank Museum, Bovington.Rear view of the Carro da 9t during trials on the beach at Sciarborasca. Note how much the casemate projects over the tracks and that this is clearly the later improved vehicle using the cast-type tracks. Source: Migia.
When the suspension was modified doing away with the large side-armor, gone were the old wheels to a new system consisting of two large bogies. Each bogie had three pairs of larger rubber-tired road wheels (connected into parallel pairs with a gap between the pair), with two main pairs connected into a single suspension shoe and the third pair on a separate arm pivoting from the mount for the other two pairs. Connected to the top of this third wheel pair’s arm was a simple flat half-leaf spring system anchored above the two fixed pairs and both bogies had this third wheel pair facing inwards. The design appeared perhaps more complicated than it was but allowed for the ‘fixed’ wheel pairs to rotate about a common pivot on their mounting shoe, whilst being partially sprung. They were followed by the third wheel pair on the sprung arm for even more capacity. With the two sprung arms facing inwards, it concentrated the springing effect of the suspension over the center line of the tank, providing more stability for the fighting compartment. It appears that the lead roadwheel from the old design of suspension, which had been keeping the track from coming back into the suspension in the gap between the lead roadwheel on the ground and idler wheel, had been discarded, but the wheel at the back doing much the same purpose had been retained.
A good view of the new suspension bogies and tensioner wheel can be seen in the prototype 10-tonne tank being evaluated alongside the Carro da 9t at C.S.M. at the same time. What is not clear is whether the suspension was designed for the 10-tonne tank and then duplicated onto the Carro da 9t or vice versa. Either way, Italy had shifted from fixed rollers to a modern spring bogie system. With the Italian Army slowly modernizing at this time, vehicle names were being changed to reflect a new military concept of operations after 9th May 1936, which categorized vehicles slightly differently.
The old CV series ‘Carro Veloce’ (English: Fast tank) series of light tanks were being reclassified as ‘L’ or ‘Leggero’ (English: Light) tanks by dint of their mass, so the CV3/33 would become the L3/33, etcetera. As the Carro da 9t was still an experimental tank at this time, it is unclear what official nomenclature would have to say on the matter, as its role was clearly one for assault and breakthrough as a ‘Carro di Rottura’. It had been named (perhaps semi-formally) as the M.33. Even if ‘M.33’ was correct and official, this would have been changed when the vehicle underwent a substantial revision for the second trials, which might suggest a second ‘M’ number. For clarity, however, the vehicle which had started as Carro da 9t is more simply considered in terms of ‘early’ (original with narrow casemate and enclosed suspension), ‘intermediate’ (with widened casemate and original suspension), and ‘late’ (modified) forms. This even allows for the fact that the weight and role had changed.
_The difference in shape for the new casemate is apparent in comparing these two photographs with the original at the top, and the new, wider casemate at the bottom.
The weight of the vehicle is also important to note. Giuseppi Rosini, the lead tank designer at Ansaldo, published a paper in 1938 making clear how weight categorization of tanks should be considered. Light tanks would be those 5 tonnes and below, whilst ‘assault tanks’ – those tanks whose role was to break through enemy lines, should be 6 to 8 tonnes in weight, and heavy tanks would have to have at least 40 mm of armor whilst not exceeding 14 – 15 tonnes in weight, all whilst still being as small as possible. The 65 mm gun as fitted to the Carro da 9t was identified as one of the two ideal weapons for a heavily armored vehicle of that weight, along with a 47 mm gun. This would mean that the Carro da 9t occupied an unusual position, being a bit too heavy for the role of a breakthrough tank or ‘Carro di Rottura’ and carrying the armament of a heavy tank, but without the armor needed to be a heavy tank.
The original all-steel track with no rubber pads appears to have been of a pressed and/or welded-type construction. It was characterized by a single hole in the center of each link into which the teeth from the drive sprocket could engage to drive it. When the suspension was reworked, available photographs also show that the track was replaced. Gone was the single hole track link and instead there was a new style of all-steel track link with no rubber pad and which appears to have been cast and which had a pair of sprocket-tooth holes. This would have been necessary to allow a center guide on the link to prevent it from slipping sideways on the new road wheels and also indicates that the drive sprocket was changed from a single ring of teeth to a more modern type with a pair of rings of teeth.
The change in track had a mobility advantage too, as the single horizontal spud on the original track was replaced on the new cast track with an integrated spud, meaning that the track was able to still obtain purchase off-road on soft ground, but also would be less likely to cause damage to a hard or surfaced road, as there was no projecting spud to dig in. Other than these changes, the essential features of the track system remained as before, with it driven by the sprocket at the rear and with the track tensioner at the front on the idler.
Comparison of the original track (left) and improved track (right). Although the improved track is packed with mud it is also clearly a different design. Source: Composite image.The Carro da 9t on a more extreme off-road trial at Sciarborasca, where the entire right-hand side has sunk into the water. The new tracks and wider casemate indicate this is the fully updated later version. Source: The Tank Museum, BovingtonThe new form of suspension, track, and casemate is apparent in this photo of the Carro da 9t undergoing tests at the Ansaldo works. The vehicle is climbing a vertical step around 1 m high. Source: AnsaldoCarro da 9t post-modification, with the new sprung bogie suspension system and the enlarged casemate. Source: Pinterest.The 10-tonne experimental tank seen at C.S.M. during testing alongside the Carro da 9t. It featured the same arrangement of 3-wheel bogies and tensioner wheel. This vehicle underwent further modification and eventually entered service as the M11/39 (11-tonne Medium tank of 1939). With a 37 mm in the casemate and machine guns in the turret, this design solved a lot of the problems of the Carro da 9t. Source: Pinterest.
The Design
The design of the Carro da 9t was relatively simple, although this belies some important features. The basic shape was a giant steep-fronted wedge with a small vertical nose leading to a large angular glacis. A casemate then surmounted this, forming a large 4-sided and roofed fighting compartment that projected over the track. It was narrow at the front and slowly widened as it went backwards. Whilst the front was the width of the hull, the rear was slightly wider. The back of the tank going from this casemate sloped away all the way to the back, after a small step down from the roof. The sloping section was slightly narrowed right at the top before widening out to the width of the hull. In this space at the back of the casemate would be two weapon mounts. Thanks to the sloping rear, these could combine to provide complete machine gun coverage behind the tank.
Layout showing blue for the mechanical section with the engine green and transmission to final drives pink. The fighting compartment is yellow and primary armament bright blue. Note that on this blueprint there are clearly just 8 roadwheels. Source: Pignato amended by author.
The entire structure was bolted internally, not riveted, to a steel frame, in much the same manner as a WW1 British tank, except that these bolts could be undone as required to remove plates. Two full-length tracks and the suspension lay behind full height side armor plates along both sides. A single Tritton-patent (Sir William Tritton, – Director of William Foster and Co.) mud-chute was present so that the inside of the track run (covered with armor) would not become clogged with mud. The track itself was exposed all of the way around the track run, with no provision at all for a track guard to prevent mud being thrown up onto the top of the tank, although the sides of the casemate did partially overhang the tracks. In this way, parallels can be drawn between this design and the 1916 design for what became the Medium Mark A ‘Whippet’, where an exposed track run clad in armor and with mud clearance chutes ran along the sides of the tank. On the Medium Mark A ‘Whippet’, there was provision for a canvas mudguard to be fitted, suspended from inverted ‘L’ shaped brackets projecting from the front and rear of the tank on each side. No such provision seems to have been made for this design, but mud would later not be able to cover the side of the casemate, as it projected over the track. The wide part of the casemate actually worked as a mudguard in this way. Behind the casemate, however, mud would still be liable to be thrown up over the grilles, into the side of the raised hull rear and exhausts.
Original form of the Carro da 9t with the narrow-fronted casemate, shielded suspension, and plate steel tracks. Source: Ceva and Curami.
Exhaust from the engine would be vented out of the right and left-hand sides of the rear hull and carried all of the way to the back of the tank, ensuring no fumes could come back into the troop space and interfere with the crew. Atop the casemate was a single large rectangular hatch that slid backward. On the left and right sides of the casemate were large rectangular access hatches. both of which opened forwards and were fitted with ball mounts for machine guns. Finally, on the front face of the casemate was the primary firepower for the design, with a single machine gun ball mount and a large ball mount for a cannon, along with a small rectangular hatch for the driver low down on the front left of the casemate. During the post trials rework, the casemate was expanded and changed shape.
The original frontal aspect of the design presented a narrow aspect to the enemy and was dominated by the large gimbal mounting for the main gun. Note that this view clearly shows that the original casemate narrows at the front to the width of the hull, matching the schematics. Source: Ansaldo.The unusual step in the sloping rear deck is readily apparent in this image showing the well angled lines of the original casemate. Source: Ansaldo.
Engine
The arrangement of the automotive parts is perhaps the most intriguing part of the design. Instead of this being a manufactured (welded, bolted, or riveted) hull with the engine and gearbox then fitted into the vehicle separately, on this design, the whole package came as one. Two steel girders would run longitudinally along the inside length of the hull from the front, where the driver would sit and operate the vehicle by means of a pair of brake levers. The driver had a simple pair of pedals for his feet and a pair of gear levers for controlling engine speed and the transmission. The engine lay directly in line, a short distance behind the driver, once more attached to this frame, and was connected directly to a mechanical transmission and final drives at the back. Again, all of this was attached to this same framework and this meant that, with the necessary parts of the rear upper armor removed, the entire automotive assembly could, in theory, be removed in one piece. In modern terms, this idea is similar to the ‘powerpack’ on an MBT, where the engine and the transmission are removed as a single piece for ease and speed of maintenance. This is nothing new in the 21st century, but was certainly novel thinking in the 1920s and 1930s. This idea would actually crop up once more from the design team at William Foster years later, with their work on the T.O.G. tanks in 1940, but was otherwise outside of the mainstream of tank designs until after WW2.
The engine originally fitted was a V6 provided by Carraro developing 85hp but was found inadequate during testing. Compared to a fast light tank like the CV33 which could manage 40 km/h, this machine would be left behind and improvements to the automotive plant were ordered. By 1935 when the tank was shown at the Fiera Campionaria di Milano the engine had been swapped to an inline 6 cylinder FIAT 355 or 355C, the same engines used in the FIAT 634N truck, developing 75hp and 80hp respectively.
Two views of the automotive framework system for the tank, with the final drives and transmission at the back, engine in the centre, and steering controls at the front. Source: Ansaldo
The offset for the driver’s position on this framework is more apparent when viewed from the front. The space to his right of the driver would be occupied by the ammunition rack for the main gun. Source: Ansaldo
Suspension
Even though the side plates on the tank preclude seeing much of what lay behind, it is clear from the arrangement of the automotive framework that the drive was delivered to the rear of the tank. The track was supported at the top by 3 return rollers hidden by the side armor plates. The weight of the tank was originally to be carried onto the tracks by 8 small road wheels directly under the body of the tank, with two more behind to support the track when the vehicle sank slightly into soft ground and a further wheel in front of the main set of wheels which also served to keep the track in place. In total, 11 wheels ran along the bottom of the track run and, in keeping with William Foster designs, as the vehicle sank into soft ground, more of the track would come into contact with the ground to improve floatation. The effect of this slight upturn meant that only 8 wheels were bearing the weight on a hard surface and the effect is subtle to see in period photographs, but it also provided the advantage of the vehicle being able to ‘slew’ (turn) more easily.
Blue shows the ground contact length when on a hard surface and Red indicates sections that come in contact with the ground as the vehicle sinks into a soft surface. Source: Pignato and amended by Author
Sadly, the details of any springing system are unclear due to the side plates. With the large void of the mud chute above them, there was no space for vertical springs. Indeed, the arrangement on the original design would appear to indicate that there was no suspension at all other than any cushioning effect from the wheels and track. It is not even clear if the wheels were simple rollers or if they were fitted with some kind of rubber tyre. Either way a fixed system would make sense, given that the Medium Mark A ‘Whippet’ was made in a very similar way with the wheels fixed into Timken bearings. Finally, at the front of the suspension was a British style track tensioner screw – again – in the same manner as that used on the Whippet.
Side view of the front-engined Medium Mark A ‘Whippet’, also from William Foster and Co. The means of track tensioner, fighting casemate, and mud chutes are all distinctive features shared with the initial Carro da 9t design. Source: IWM
A close examination of the available photographs for the vehicle during development show that the original suspension appears to have been changed from that initial 8 + 2 fixed wheel system to a spring-based system with 9 or possibly 10 wheels all positioned slightly behind a fixing point on the side armor suggesting the side armor point is the end of a pivot for an arm on which the wheels were mounted. That, in turn, suggests the springing system employed was a vertical coiled spring and with tensioning wheels between these suspension road wheels and the idler and sprocket.
Seen in side view, the relatively low profile of the design is apparent, along with the distinctive side armor plates over the suspension. The large mudchute is interrupted only by the large stowage box roughly centrally on the length of the tank. Source: Ansaldo With the engine and casemates edited out, the similarities of design on the track systems are readily apparent for the British Medium Mark A Whippet (top) and the Carro da 9t (bottom).Note the position of the wheels in the bottom image in relation to the mounting points ahead of them on the side armour. Source: Composite imageScheme taken from Sir William Tritton’s patent of 1919 for improved armor within a suspension system for a tank. Pink is the top and bottom of a track run, whilst blue is the side of the hull. Green is the angled plate within the run which provides additional armor protection to the hull side and also serves to move mud falling from the top tracks out and away from the tank. Source: Adapted from British Patent GB126671Front ¾ view of the Carro da 9t shows to good effect the side armor plating over the suspension. In this image, the mudchute has been removed, as has the side stowage box. This view clearly shows that there is no vertical spring system installed in the space behind the angled plate. Note that this is clearly the reworked casemate, as distinguished by it being wider, overhanging the new tracks, and characterized by the addition of triangular sections on each front corner. Also note the early production CV3/33 to the left of the shot. Source: Ansaldo
Crew
At least two crew were needed for the tank, with one man necessary to do all of the driving from his seated position low down in the front left of the tank. His vision was limited to just straight ahead, either through the rectangular hatch or, in combat, with the hatch closed, through a single vision slit in the hatch. No vision slits were provided in the sides of the casemate for the driver, so, for additional information, he would have been dependent upon the commander or other crew members. A single wide vision slit transected the driver’s rectangular hatch in the front so he could see out whilst under fire and a second, smaller slit was provided in the front above the machine gun mount. Additional vision slits were provided in the rest of the casemate above the other ball mounts with the exception of the main gun. A second crew member was the operator for the main gun on the right hand side of the cab. In order to keep the breech clear, for his own safety, or to load, he may have simply had to stand to the left of the gun, approximately in the centre-line of the casemate.
The main gun mount featured a large sighting optic to the left which could be fixed to move with the main gun within the ball mounting. It is likely that there would have been a third crew member who would have been tasked with operating the front machine gun which was likely removable, so it could be used in one of the other mountings as needed. Whether this crewmember or the one with the main gun would be the vehicle commander is unclear, but given the very low visibility for the man on the left, with just three small vision slits, it seems more likely that the main gun operator, with the large moveable optic, was a better choice, even if operating the gun and commanding was not an optimal combination of roles.
The ammunition rack, located on the front right, alongside the driver, was below and forward of the gun breech, which would have made reloading by the commander awkward. It is likely that the second man would act as a loader when not busy with the machine guns or, when static, these would simply be passed to the gunner by the driver.
Contemporary artist’s side view inside the Carro di 9t. It clearly shows the original form of small wheel suspension, but also just two crewmembers, with one wearing a very non-standard and rather Buck Rogers’ style tankie helmet, similar to some helmet experiments being carried out for the Italian Army at the time. Also of note is that this drawing clearly shows just 7 road wheels. Source: Miglia
The commander had no specific optical devices on the roof to assist in observing his surroundings but would have been able to see sideways through the vision slits in the machine gun ball mounts, as well as forward using the telescope on the main gun or by eye through the vision slits. If needed, although hazardous in combat, he would also have been able to observe the enemy out of the roof hatch, although this would also mean he would be unable to operate any of the tank’s weapons at the time. The only available photograph of the tank with a crew also only shows two men, so this appears to confirm the tank had only a crew of two.
Armament
Firepower was an important consideration for this tank design, as it would need to not only tackle defensive positions for its breakthrough role, but also enemy infantry. The infantry-killing part of the armament was managed by means of five machine gun ball mounts, with one placed on the upper left side of the casemate, another two in each of the side doors, and two in the rear of the superstructure. No machine gun was mounted on the roof, as was common at the time on Italian tanks. Lacking a turret, the tank also had to rely on the pair of ball mounts in the rear of the casemate, or pull a machine gun from the front or side mount and deploy it out of the roof hatch by hand to cover the rear.
As the sides of the casemate were actually sloping forward slightly, the ball mounts there could deliver limited fire at perhaps as much as 45 degrees to the front as well as across both sides, at the price of a little coverage to the rear.
Looking into the tank with the original casemate, as seen through the left-hand side access hatch. This provides a clear view of the breech of the main gun, as well as the fighting space. For just two men, this would have been relatively spacious. Note that the telescope is clearly not fixed to the main gun and can be moved independently in the vertical axis. This photo also clearly shows the method of manufacture was mixed bolting and riveting, with the main armor sections bolted together onto a metal frame and the lower hull all riveted. Rivets are also used for smaller features within the bolted panels. Source: Ansaldo
An ammunition rack for the main gun was provided in the front right of the hull, alongside the driver. It was angled upwards toward the inside to facilitate the shells being retrieved and used by the operator. With a capacity of 35 rounds, the rack was also notable in that it was a metal shielded rack to protect the shells from spall from the armor, but is not fitted with protective doors over the back of the shell casings. Looking inside the original casemate, it is clear as to why it was widened. There was simply insufficient side space available for either the main gun to be rotated to the left, where operation of the breech would be impinged by the sidewall, and for the machine gun on the front left being turned to the right. Space under the crew seating in the back of the casemate would allow for crates of additional ammunition to be carried. Historian Fulvio Miglia places the total ammunition capacity at 80 rounds for the main gun, along with 3,000 rounds of machine gun ammunition although is likely a guestimation based on the dedicated rack and storage space.
Photographed through the sliding roof hatch down into the fighting compartment, the driver’s seat can be seen down on the left-hand side. The breech of the 65 mm gun, with its telescopic sight, dominates the compartment. Next to it is the forward-facing machine gun in its own mount. Two seats appear to be visible at the very bottom left and right of the photo, meaning another two crew in the fighting chamber. Note that this photo shows that the expansion of the casemate was not done in order to fit a third man, as this is the original casemate shape. Source: AnsaldoPlans for the 65 mm mounting in the Carro da 9t dated 1930, clearly written as “Carro d’Assalto”. The small size of the weapon is readily evident, as is the rear protrusion into the fighting chamber, showing it could be mounted and operated with a man behind it. The sighting optic to the left of the gun is not shown in this image. Source: MigliaThe main gun in its large hemispherical gimbal mounting as shown on a test rig. The outer part of the ball can rotate left or right and, inside this, is the second smaller dome fixed to the gun and mounted to the outer portion by horizontal trunnions, allowing for vertical movement. Source: MigliaSeeing inside the casemate via the right-hand access door shows a rather spacious, albeit spartan interior dominated by the periscope and breach for the main gun. Source: Miglia
The 65 mm gun to be fitted was not, as might have been expected, the 65 mm L/17 Turin Arsenal M.1910/M.1913 mountain gun which had been fitted to the FIAT 2000 a generation earlier, and which was still in service with the Italian Army. In 1926, that gun had been removed from its role as an infantry support gun and passed to the mountain troops due to its compact size and weight. Despite its age, it was still an effective weapon for throwing a high explosive shell out to 6.5 km. That gun remained in service even through WW2 but, at 17 calibers (1.15 m) long, this was not the gun fitted in the Carro da 9t. The surviving drawings for the gun show the weapon to be substantially shorter than 17 calibers. Measuring pixels off the drawing, it is approximately 7 (measured as 6.8) calibers from muzzle to breech. The drawing also shows only a single type of ammunition as a solid shot, which would have been of little use against a fortified position, where an explosive shell was needed.
Pixel counting gives approximate dimensions for the gun. A very short-barrelled 65 mm piece. Source: Miglia as amended by the author
On the 65 mm L/17 gun, the high explosive shell was supplemented by two types of shaped charge shells, all of which were useful against armored or protected targets, but also an armor-piercing shot as well. That 4.23 kg shell was limited to an effective range of just 500 m and these shells were fired at between 320 and 355 m/s. With a shorter barrel, it could be expected that this 65 mm gun would have an even lower velocity. This would make no difference to the effect of a high explosive shell other than flight time to the target, but would impact the effectiveness of any use of the solid AP shell for anti-armor work. Assuming 65 mm shells from the 65 mm mountain gun, which were plentiful in Italian Army supplies through the period, were compatible with this one, then ammunition options would include high explosive (HE), shrapnel, canister, armor-piercing (AP), and ‘Effetto Pronto’ (rapid effect) shaped charge shells.
The gun is, however, a confusing issue. Whilst the model and indeed the plans both show this very short-barrelled 65 mm gun (~7 calibers), the gun as fitted on the constructed vehicle is clearly longer than this.
The model (top left) and the Ansaldo blueprint (top right) do not match the actual gun fitted (bottom). Source: Composite image
The 65 mm Model 13 mountain gun was 17 calibers long and was available, but this is also clearly too long to be the gun that was mounted in the casemate. This leaves open the question of exactly what the gun was. It might be suggested that the gun was a cut-down version of the M.13, but the breech of that cannon does not match either the available drawing or photographs. The gun as fitted is assumed to be between 7 and 13 calibers long and estimated as an L10 caliber gun.
65 mm L/17 Model 1913 Mountain gun. Source: Italian Ministry of Defence
Interior photographs of the Carro da 9t prior to it being rebuilt with a wider casemate appear to show a FIAT-Revelli Model 1926 machine gun. A 6.5 mm caliber weapon, the gun was fed from a 20 round box-type magazine from the left-hand side. On a ground mount, the machine gun came with an unusual crutch-shaped stock, but this was unnecessary in the fixed ball mount, so was not fitted.
These views of the machine fitted in the casemate prior to the rebuild show what appears to be a FIAT Model 1926 6.5 mm machine gun. Source: Composite imageSeen during Italian trials, the tank has the driver’s vision flap wide open and the right-hand side door also appears unfastened, presumably to help with ventilation. Source: PinterestTwo Italian ‘Carristi’ (English: ‘tankies’) with the Carro di 9t during trials in Italy. Note that the vehicle is still fitted with the full side plates over the 9-wheel suspension. The use of the side-entry hatch would still be a feature of Italian medium tanks through the war.
Armor
Exact specifications for the Carro da 9t armor are not known but, between photographic evidence, logic, and the protection requirements, estimates can be made. The Medium Mark A Whippet had armor up to 14 mm thick – sufficient to keep out bullets from rifles and machine guns, but not cannon fire. Rosini, in his 1938 paper, notes that at least 40 mm was needed to provide protection from 20 mm cannon fire and the 10-tonne to 11-tonne M11/39 settled on 30 mm for the front and 14.5 mm for the hull sides. Clearly, 40 mm could not be achieved on even the front of the Carro da 9t and given its weight of 9 tonnes. The 3-tonne CV3 series of light tank had 14 mm on the front, going down to 8 mm on the sides. The Carro da 9t would clearly need to have at least that level to be viable. It is logical that the sides of the Carro da 9t at least roughly matched the M11, at around 14 mm, as less than this would render the vehicle vulnerable to fire from the flanks.
The thickness of the side casemate armor is apparent in this image. Source: Ansaldo
The Lessons from Spain
The original project had been for little more than a new powerful tank to refight much of the experiences of WW1, but times and weapons had changed dramatically in the years since 1919. Italy had gone into the Spanish Civil War with outdated equipment. One of the key lessons from the Italian involvement in that war was the need for a tank to have a turret. The Italian CV3 series light tanks (derived from the CV29) had been used and found to be outclassed by the Soviet-supplied T-26, a tank ironically derived from the Vickers 6-ton, which had been rejected by Italy in the early 1930s.
During this time, other developments for tank design had taken root in Italy with the 1935 requirement for a tank capable of operating in the mountainous north of the country, weighing just 8 to 9 tonnes. In this sense, the Carro da 9t can be seen as less desirable as a design to be pursued for mass production.
Pictured during testing, the Carro da 9t shows the side armor skirts have been removed, exposing the modified suspension. The vehicle on the left is the 10t experimental vehicle which would become the M11/39 and was emblematic of Italy’s struggle to move from casemated tanks to ones with the primary weapon in the turret. Source: Pignato
By the end of the 1930s, the Carro da 9t formed part of the lessons being adopted by Ansaldo for how to arm tanks. Putting all of the firepower in a casemate was problematic in terms of where firepower could be delivered, but it did produce a low-profile tank.
The two armament mounts of the Carro da 9t, as drawn in 1938, showing the influence of this vehicle was still being felt even if this method of weapons mounting was considered obsolete. Source: Rosini
A final chance?
The Carro da 9t did not go anywhere in Italy. By the time it was finished, tested, trialed, and modified, a better option was available in the form of the 10-tonne/M11/39 project. Still carrying a cannon in the hull (albeit a 37 mm and not a 65 mm or 47 mm piece) and with a turret for all-around machine gun coverage on a smaller profile vehicle with better suspension, it was better in almost every way than the Carro da 9t. What had started as a design in 1929 for a tank of the 1920s was, by the mid-1930s, a dead end. By the time the Italians had finished testing it, it was little more than a testbed from which to draw lessons in vehicle design and weapons, so it is perhaps surprising that this was not the end of the road for the design.
In 1940, Sir Albert Stern, best known as chairman of the Special Vehicle Development Committee (S.V.D.C.), who worked closely with Sir William Tritton and William Rigby, offered this design to the British Tank Board. Quite why this design was even mentioned is unclear in the context of conversations outside the recorded minutes of the meeting. The design in no way met any of the criteria for a tank the Board wanted, so it can only be speculated that it was simply as a concept for how a bigger gun could be put onto a smaller vehicle as some kind of casemated mounting. Either way, the idea was not entertained, and using this design was not mentioned again.
Conclusion
If the goal at the end of the 1920s had been for a small light tank capable of penetrating enemy lines, then the design from William Foster and Co. was hopeless for that. Heavier than the Renault FT it was to replace, it had barely more armor and was, in effect, still a WW1 era design. The vehicle was never going to square the circle of conflicting needs for a light breakthrough tank. The development and testing took so long that events outside Italy simply rendered it obsolete before it was finished. Italy was going to need a turreted tank with a good gun, but what it was left with after the failure of this project was little more than the starting point for another obsolescent tank, the M11/39. The failure to invest in the interwar period and the lack of industrial capacity to make up that shortfall in the years running up to WW2 meant that Italy entered the war with a stock of outdated vehicles and struggled continuously to get a modern vehicle to the men who needed it. In an era of military cutbacks in vehicle design and development, lessons from this era and what happened to Italy should serve as a reminder for what happens when you fail to invest or prepare.
The Ansaldo Carro da 9t seen from the side. Illustration by Pavel “Carpaticus” Alexe
Specifications Carro da 9t Crew: at least 2, but probably 3 (driver, primary gunner/commander, machine gunner) Dimensions: 4.9 m long, 1.8 m wide, 2 m high. Ground clearance: 0.37 m Weight: 9 tonnes Armament: 65 mm, 2 machine guns (6.5 mm FIAT-Revelli Model 1926) Ammunition: 80 rounds (65 mm), 3,000 rounds (machine gun) Engine: Carraro V6 85hp – FIAT 355 75hp or FIAT 355C 80hp.
Commonwealth of Australia/United Kingdom (1939)
AFV – None Built
Budgong Gap may not be the sort of world-famous location associated with great architecture or magnificent structures of the ancient world. Nor is it a place with any association in the world of armored fighting vehicle manufacturers, yet this somewhat obscure location, lying nearly a 3-hour drive south of Sydney, New South Wales in Australia, does have one claim to armored vehicle fame – the Gerreys. World War 2 broke out for Great Britain on 3rd September 1939, when it declared war on Germany after the Wehrmacht had invaded Poland. Australia followed suit, with Prime Minister Robert Menzies announcing that Australia was also once more at war. Within a month, the Gerreys had submitted a design for their own tracked and turreted weapon of war. Looking like a tracked motor car with a turret, the Gerrey design is perhaps yet another of those well-intentioned designs submitted in wartime but is also one of, if not the first of Australia’s homegrown armored vehicle designs of the war.
The Gerreys
The Gerrey family were ranchers/farmers from a very rural part of Australia and had been established in the area from at least the turn of the century.
The two inventive members of this family were Bernard Bowland Gerrey and James Laurence Gerrey. Although it is not known what their relationship was, it is surmised that they were brothers. Both men gave their occupations in Budgong Gap in 1939 as Timber Hauliers. Bernard had previously been in the National Press in 1931, relating of a possible sighting of the wreckage of the Southern Cloud, an Avro 618 which was lost in bad weather in March that year over densely forested wilderness. There would be no fame or reward for Gerrey for that foray into the public eye and the plane was not found until 1958.
The Design
In October 1939, when the Gerreys (both Bernard and James) submitted their design, the vehicle was intended to fulfill a single simple objective – to provide a “motor propelled armoured vehicle” with a turret “in which a series of automatic machine guns are mounted in superposed groups”.
Shaped like a giant boot, the vehicle effectively had the appearance of a tracked saloon car with a giant cylinder sticking up on the back of it. Access to the vehicle was via a pair of large rectangular doors on the right-hand side of the vehicle. The left side is not shown in the drawing, but it can be assumed that these doors were duplicated on the left side as well. The first door was directly accessing the cab area of the ‘car’ part of the vehicle, roughly halfway along the side. The second door was at the back of the vehicle, below the cylindrical turret. Judging from the size of the doors, it would indicate enough space inside for perhaps as many as three men, although a crew of two is perhaps more reasonable as only one man would be needed to drive the vehicle and another to operate the weapons. One final note on access is what appears to be a series of 5 or 6 parallel steps on the right-hand side (and presumably the left as well to match). These steps were on the sides of the vehicle running vertically just behind the door to the driver’s position and running up to the roofline. There appears to be a third hatch shown on the side view just above and behind the side door as well, although it is neither mentioned in the text of the patent application nor in the plan view drawing.
Outline of the Gerrey Machine Gun Motor Vehicle, as modified from the Patent image by the author.
The other very notable feature of the design is the very elegantly sculpted cowls for the pair of headlamps on the wings of the vehicle over the tracks. Such a design feature provided zero military advantages and was clearly inspired by a civilian style of automobile instead.
A crew of two would also match the plan view of the vehicle, which shows just a single opening in the front for the driver and no such opening or weapon on the left of the cab to indicate the need for a second crewman in the ‘car’. Likewise, in the turret, the plan view clearly shows a tractor-style seat for the weapon operator to sit on, indicating just a single man in the turret. At most, therefore, a crew of three could be hypothesized with the third man presumably languishing inside the passenger side of the ‘car’, occupied perhaps with managing a radio.
Both the 1931 report of a possible aircraft sighting and their employment as Timber Hauliers in 1939, as well as the rugged terrain in which they lived, indicate that they should have had at least a working knowledge of vehicles off-road, such as log-hauling tractors. This may account for the flat style of tracks used, as they have the appearance of the type more associated with industrial plant-like crawler tractors and even tracked cranes than the sort of tracks associated with military vehicles, which usually have a well-defined and raised leading front edge for the track.
Indeed, the flat style of track selected is not usually a problem on industrial machines, as the front and back of the bodywork rarely project the way they do on this vehicle. The projection over the back of the vehicle would, for this design, severely limit the steepness of a slope that could be climbed and likewise, at the front, the projecting bodywork would foul on the ground reducing trench crossing ability. This is perhaps the most surprising weakness of the design of the machine from the Gerreys.
Automotive
The ‘car’ shape of the body of the vehicle is misleading, as the means of propulsion is decidedly not-car-like. Instead of running on rubber-tired road wheels, like a normal passenger motor car, this vehicle instead used a pair of full-length and rather narrow tracks. The Gerreys described the means of propulsion for these tracks as consisting of an “internal combustion motor of ordinary type and associated with the usual driving and change speed gear”. However, despite showing the vehicle on tracks, the Gerreys also suggested that this type of turret and armament system could be mounted upon “any kind of transport vehicle”.
The side view available from the patent indicates 20 or so large flat links per track with power delivered via a toothed sprocket located at the back. Each link is overly large for such a small vehicle with a large pitch and would indicate that the vehicle would have serious limitations on its top speed. Likewise, the positioning of the drive sprocket and idler, both in contact with the surface, would create a most uncomfortable ride even if there was any suspension shown or described, which there was not.
The engine, as shown in the plan view, lay at the front, under the bonnet, as would in the case of an ordinary passenger motor car, with the radiator in front of it. In order to protect the radiator from enemy fire, a set of hinged and moveable plates were fitted to the front, which could be opened in order to access the radiator and also allow more air in to improve cooling. Although the lines of the front of the car suggest a bonnet that could be opened in order to access the engine, there is none showed, which would mean a difficult time for anyone trying to do maintenance on the vehicle.
Armament
The primary weapons for the Gerrey design were a series of automatic machine guns. All of them were connected together in the wall of the turret and provided with a slot or other opening through which the barrels could protrude. All of the machine guns could be operated by a single crewman using a simple one-pull trigger, firing all of them at the same time. This wall of fire was no doubt an impressive thought. Assuming perhaps a rate of fire of 600 rounds per minute from each of the unspecified machine guns, it would be essential that each one was fed by a belt, or else the only job of the gunner would be changing magazines. With three rows of machine gun pairs fitted within the large cylindrical turret, a total of at least 6 machine guns (and as much as 18) are shown with their barrels projecting from small loopholes. Six machine guns firing 600 rounds per minute would be 3,600 rounds per minute fired in the general direction of an enemy through a narrow opening, allowing for very limited vertical movement of the guns.
As the vehicle, as drawn, would be using weapons compatible with British supplies, it would suggest weapons like the Browning machine gun and a bullet caliber of .303 or 7.92 mm, like that fired from the BESA machine gun. Belts for the Browning machine gun came in lengths of 500 rounds with two belts to a crate. Assuming the crates or boxes were dispensed off, the weight of the ammunition alone to serve these weapons is a significant burden the Gerreys failed to take into account, as one belt alone weighed in the region of 7 kg. One minute of sustained fire therefore would demand:
((No. of guns x rate of fire) / rounds per belt) x weight of belt
((6 x 600) / 500) x 7 kg = 50 kg of ammunition per minute
That is 50 kg of ammunition per minute, so even a modestly useful combat load of just 10 minutes-worth of fire would mean carrying half a tonne in ammunition alone. For anything other than perhaps anti-aircraft work, the six machine guns were simply adding the weight of the guns, complexity of the mechanism, and weight of the extra ammunition for no particular benefit. Given that the design of the Gerrey vehicle would preclude the anti-aircraft option due to the limited elevation of the guns, it has to be considered that a far more useful and practical arrangement of the firepower from this vehicle would have been served with just a pair of machine guns.
It was, however, these superimposed rows of automatic weapons, all operated by a single person, which was the crux of the patent invention, as they felt that this style of turret was both novel and important. Thus, the Gerreys patented something novel but inherently unusable.
Plan view taken from British Patent GB537405 showing the engine and radiator at the front and the protective covers over the front grill. Note the vehicle is right-hand drive, as would be expected from a British or Australian vehicle. The single-seat for the gunner and the array of automatic weapons in front of the seat can be seen in the turret, shown facing backward. Source: British Patent GB537405Plan view of the layout of the Gerrey’s machine gun motor vehicle taken from the patent and cleaned by the author to remove annotations and interior. The radiator shutter has also been added. Source: British Patent GB537405 as amended by the author.
Protection
Few specifics of the armor on the vehicle were described in the patent application, other than to say that the chassis was relatively lightly armored. From this, it can be inferred to be protection against small arms fire rather than the type of protection that would be needed against anti-tank shell fire.
The turret was sat recessed slightly into the body of the vehicle, which would reduce the chances of it being jammed by enemy fire and prevent splash from entering the vehicle through the gap.
Conclusion
The vehicle submitted by the Gerrys was a simple one, well within the technical abilities of the day to produce, but it was also redundant and somewhat naive. Even assuming the engine would have had sufficient power to propel the machine off-road, it was poorly laid out in terms of using space and was therefore going to be heavier than it needed to be. The same is true of the mechanism in the turret – heavily burdened with large gearing more akin to a heavy drive system than one for simply moving and firing machine guns.
They may be excused for some lack of knowledge when it comes to tank design, but it is hard to explain how they might see this vehicle moving across the sort of terrain they would have been familiar with. Overall, the design is crude and relatively poor, showing a great deal of naivety when it came to military vehicle design, with poor use of space and layout. The inherent problems of command and control between the driver and gunner and the excessive multitude of weapons would make any serious operation of the Gerrey vehicle problematic, to say the least, and likely one which would not be able to be operated efficiently under the stresses of combat. Indeed, only the US Army of the era might have been interested in a machine with such a preposterous number of machine guns, but regardless of the military faults, it is the tracks that are the biggest surprise.
For a pair of men who clearly have experience outdoors and almost certainly had seen or used vehicles in that terrain, it is easy to imagine the inspiration for the shape of the tracks they selected. What is less clear, however, is why the overhangs were not identified as a problem.
Nothing became of the design from the Gerreys, which is not really much of a surprise. As skilled as they may have been as timberers or as rugged outback pioneers, their ideas, whilst well-meaning, were simply too naive, too crude, and not fully thought-through – they simply were not what Australia or Britain needed in the war. This design, unofficial as it was, at least started the multitude of ideas coming from Australia for its own armored vehicle programs. Forgotten perhaps almost as soon as it was patented, the vehicle is little more than a short misstep in Australia producing what eventually became a very competent independent tank program. What became of the Gerreys is not clear, but they seem to have dropped their military ideas, submitted no more patents, and likely returned to what they knew best.
Illustration of the Gerry Machine Gun Motor Vehicle. Illustration by Yuvnashva Sharma, funded by our Patreon campaign.
Sources
British Patent GB537405, ‘Improvements in Armoured Motor Vehicles provided with Machine Guns’, filed 16th October 1939, granted 20th June 1941.
Kangaroo Valley Voice July 2008: An insight to life back then.
New South Wales Parliament, Proceedings of the Legislative council Votes and Proceedings Volume 6
The Sun (Sydney) 11th July 1931 ‘Southern Cloud Search’
Northern Times (Carnarvon) 16th July 1931 ‘Wreckage of Plane Discovered’
Sidney Morning Herald 25th October 2019 ‘From the Archives, 1958: The Southern Cloud mystery solved after 27 years’
United Kingdom/Republic of Poland (1944-1945)
Armored Carrier – Design Only
Poland had been crushed in WW2. Hitler had invaded Poland from the west on 1st September 1939, followed by a Soviet invasion from the east 16 days later. Despite dogged resistance, it was all futile and the country was split between the two ideologically opposing powers. Thousands of Polish nationals and soldiers had, however, escaped the invaders and many of them fled to Great Britain, which had declared war on Nazi Germany on 3rd September, although not on the Soviet Union following their part in the invasion. With their country occupied and terrorized, many of the escaped and exiled Poles and Polish nationals living in the UK either joined up with the British to fight for a free Poland or put their skills to use in other areas, such as inventions or contributing to war production.
One Polish national, Stanisław Sochaczewski, would submit an idea for an improved armored carrier in concert with a British woman and would produce an unusual idea for a variation on the Universal Carrier.
The People
Isabel Smeaton (British) and Stanisław Sochaczewski (Polish) both provided an address of 4 Clarence House, London, for their September 1944 patent application for improvements in motor vehicles. The relationship between them is unclear, and we have no information of either of them except that Stanisław Sochaczewski could be General Stanisław Zygmunt Sochaczewski (27/8/1877 – 14/7/1953), a retired Polish Army Officer who had been living in Britain since May 1939, where he was a critic of General Władysław Sikorski. General Sikorski was the Prime Minister of the Polish Government in exile starting from September 1939 and Sochaczewski’s criticism of Sikorski even led to Sochaczewski being imprisoned in Scotland for a short period of time.
General Stanisław Sochaczewski 27/8/1877 to 14/7/1953. Source: Wikimedia Commons
This was not Sochaczewski’s first attempt at a small carrier-type vehicle. In December 1943, he had sent a somewhat self-aggrandizing letter to the War Office suggesting what he called ‘Armoured Trolleys’, roughly the size of a Universal Carrier, which could be used to rapidly assault enemy positions. Evaluated by the Canadians, that suggestion had rightly been rejected as impractical. He had, however, ended that letter with a hint of his thinking – thinking which would shape this application with Mrs. Smeaton.
“During the few weeks taken by polishing up and duplicating which has been said above [his idea for the Armoured Trolley amongst others], there has been disclosed that an armoured fighting vehicle [emphasis added by Sochaczewski] which is perfectly suitable for the purpose described is already developed and mass produced. It is the British Army’s Universal Carrier (Lloyd-Carrier) [sic: Loyd Carrier] which can very easily be accommodated for carrying in a comfortable prone laying posture not three as had been suggested, but five-men, in two layers; two Bren-gunners below and three automatic-riflemen on top of the latter, all comfortably posted, fully protected by armour, aiming through periscopes and, if there is need, fully covered from bullets or splinters coming from above (very important for the street fighting and under strafing air attacks).
When out of enemy’s fire, men are comfortably sitting and there is plenty of room for fuel, ammunition and water. No better accommodation can be found”
As it happened, Sochaczewski was to tone down the prospective crew of 5 to just 3 for his patent application, but it cannot be left unremarked that he was somehow unaware in late 1942 of the existence of the ‘Universal Carrier’.
Sochaczewski’s Armoured Trolley with an outline of a standing soldier for scale. Based on this drawing the vehicle would be a little over a meter high. Source: Canadian Archives
Design
The goal of the design was the production of an armored vehicle using tracks that could be used to haul a number of men and their equipment safe from enemy fire as well as allowing them to position their weapons to facilitate fire on the enemy.
To create this vehicle, an open-topped armored box-body was formed from two sections, allowing for men to sit or lay at different heights. In normal usage, the men inside would sit upright for comfort but for protection would be able to lie down inside and still operate the vehicle. The body was described as:
“The vehicle comprises an armored body, mounted on an undercarriage composed of a plurality of wheels and an endless track of known form, which undercarriage constitutes no part of the present invention”
What this meant was that their invention was not for a complete vehicle in its own right, but a modification to an existing vehicle and the obvious visual similarity here to the Universal Carrier-type vehicle is unmistakable although, it should be clearly noted that, with four road-wheels, the design actually most clearly matches the American-built T16 carrier rather than the 3-roadwheel carrier
The body would be new, to facilitate the new and improved layout and protection, but the running gear, suspension, and tracks would be the same.
The seating in the back of the vehicle was to go on top of the sponsons, forming two rows of bench seating behind the driver’s space in the front. Using removable covers for those benches and rolled matting meant that, if the vehicle went into combat, then the benching could be quickly folded up, the matting unrolled and the men lay down in relative comfort. The compartment was also arranged with a type of false floor forming a shelf. This allowed for one soldier to lie at the lower tier of the vehicle, with another on the shelf above him, meaning more men would be able to face forwards to fire.
Front view of the carrier showing the three firing positions. Source: UK Patent 568636
The driver, however, was different. In normal driving, he would be sat up like the others, but in combat, his seat would recline backward so as to position him in a semi-lying position. This, therefore, is one of, if not the first use of a reclined driver’s station for an armored fighting vehicle. This is something considered a significantly valuable feature of the Chieftain main battle tank and still in use as a concept today.
At the back left-hand side of the vehicle, there was a protected space, under the stowed sections of roof armor for the stowage of stores, and ammunition.
Side view of the carrier with the crew in ‘normal’ positions (top) and combat positions (bottom). Source: UK Patent 568636
Automotive
No specific engine was detailed in the design, but it was positioned in the rear center of the vehicle, with fuel tanks on the right side of the rear section, with a reserve oil tank on the right side above the sponson. Although no claim over the suspension system is made, the notable exception to anything being mentioned is the transmission. On the Universal Carrier, the rear-mounted engine was connected by a drive shaft to a transmission mounted across the front and, although there would still be room on this design for the transmission in the front, it would have been a tight fit against the face of the lower man. The other option perhaps was to put the transmission in the rear, but none of that was mentioned by the designers, who were preoccupied with layout and fightability.
Armor
No thicknesses of armor were specified in the patent and the vehicle was nominally open-topped in much the same style as the ‘Bren’ or ‘Universal’ Carrier. During normal operations, the men sat upright but, for combat, the men could lie down inside. The armor at the front was shaped in such a way as to provide a convenient aperture for the rifles, providing a rest for them. Although there is no thickness, the designers wanted the frontal armor to consist of two main plates, with the upper of the two fitted with two gun apertures and the lower plate with just one. The low-tier man would be able to fire from the lower aperture and the two upper-tier men from the upper two apertures. To allow for better traverse of fire, each aperture was also provided with a second plate to overlap the edges of the armor around each aperture to ensure that no gap was permitted.
Adding to the overall protection was the provision of moveable roof armor stowed at the back of the vehicle, which would be brought forward covering the roof of the vehicle when the men were lying down. No hatches were provided, so, to get out, the men would simply have to move up or back the armored roof plate. If this vehicle was to roughly match the Universal-type carrier’s armor would be bulletproof, up to 10 mm thick or so.
Top-down view of the Smeaton/Sochaczewski carrier showing the position of the two men on the top tier and below them just visible the front of the man on the lower tier. Source: UK Patent 568636
Armament
No specific armament other than rifles is mentioned in the patent. Four men, with one driving, meant potentially three weapons facing forwards at the same time and, although the British .303 SMLE was a famously quick-firing bolt action rifle, three such rifles was not a tremendous amount of firepower, especially considering the ‘Universal’ or ‘Bren’-type carrier was usually seen carrying a Bren .303 light machine gun (LMG).
British .303 caliber Bren light machine gun. Source: Wikimedia Commons
The side view of the combat positions, however, clearly shows that the lower position was drawn with a weapon using a curved magazine coming out of the top and a distinctive flared muzzle – features matching the Bren LMG. If this was the case, then the armament would be limited to just a pair of rifles in the top tier and a light machine gun below them.
Other work
Isabel Smeaton is hard to track down but, as of September 1944, was likely still living at 4 Clarence House, as there is a recorded death of a John Stuart Smeaton (presumably her husband or father) on 7th July 1944. His occupation was given as a ‘sanitary engineer’. It was with John Smeaton that both Isabel and Stanislaw had submitted a patent application back in January 1942 for a small mirror system for shooting from behind cover and reference was specifically drawn in the carrier-patent to that design. Other inventions of war time relevance involved training devices for the army but, as far as can be ascertained, none of them were successful.
Design for a small mirrored device to allow a rifle user to shoot from behind cover. Source: UK Patent 555356
Conclusion
The work of Smeaton and Sochaczewski on this carrier had taken a lot of thought to try and consider the problems of improving protection and fightability. Creating a roof, adding firepower and useability were all good and noble ideas. Several key factors of note within the design were particularly credible such as:
Removable flooring rolled up when not in use
Removable benches
Interior divided longitudinally into compartments
Driver’s seat able to adjust from sitting up to a reclined position
Armored movable roof plates to protect the men from above
Additional apertures for rifles and/or other weaponry in the front
The problems with the design are readily apparent, however. The vehicle was never going to be of significant combat potential and all that work to create an extra tier of firepower when a simple Vickers machine gun on top would more than quadruple the firepower of the existing vehicle without having to completely retool a manufacturing line for the tens of thousands of carriers produced. None of these Smeaton Sochaczewski carriers were ever made, as the design simply offered far too little to warrant replacing a mass produced vehicle already in widespread use.
Illustration of the Smeaton Sochaczewski Carrier by Yuvnashva Sharma, funded by our Patreon campaign.
Smeaton Sochaczewski Carrier specifications
Crew
1 (driver) – up to three more fighting men
Propulsion
unknown
Speed
unknown
Armament
2 x .303 rifles and 1 x .303 light machine gun
Armor
~bulletproof
Sources
Universal Carriers https://www.canadiansoldiers.com/vehicles/universalcarriers/universalcarriers.htm
UK Patent 568636 ‘Improvements in or relating to Armoured Vehicles, filed 6th September 1944, granted 13th April 1945
UK Patent 645416 ‘ Improvements in automatic small arms’, filed 11th December 1947, granted 1st November 1950
UK Patent 627207 ‘ Improvements in or relating to Recoil Operated Small Arms’, filed 21st August 1946, granted 3rd August 1949
UK Patent 555356 ‘ Improvements in or relating to Rifles and Like Guns’, filed 18th February 1942, granted 19th August 1943
UK Patent 567121 ‘Improved Wheeled Carrier for Bandoliers or Belts Packed with Ammunition’, filed 14th July 1944, granted 29th January 1945
UK Patent 540079 ‘Improvements in or relating to Appliances for Musketry and the like Training’ filed 27th March 1939, granted 3rd October 1941 (address formerly Mokotowska No.3, Warsaw, Poland – now at 20 Chesney Court, Shirland Road, London W9)
Biography of Stanisław Zygmunt Sochaczewski at iPSB https://www.ipsb.nina.gov.pl/a/biografia/stanislaw-zygmunt-sochaczewski
Sochaczewski, S. (1943). New Fighting Equipment – Modified Infantry Tactics. London 1943. Canadia Archives Reference C-5829: 55/6276/1
The London Gazette, 22nd September 1944, page 4419
United Kingdom (1940)
Amphibious Tank – Design Only
The Old Gang (TOG) was an informal and perhaps derogatory name applied to the men who had been primarily responsible for delivering British tank designs in WW1. With a new war started in 1939, these men, under the leadership of Sir Albert Stern, were formed into the Special Vehicle Development Committee (S.V.D.C.), although they soon adopted the TOG moniker as a badge of honor. More commonly known for work on the large heavy tank projects TOG-1 and TOG-2, the SVDC were actually a body utilised for their expertise for a number of projects and one of those, in the Summer of 1940, was the need for an amphibious tank.
With a flair for design and the ability to work unencumbered by the normal military and political bureaucracy, the SVDC delivered one of the most unusual ideas for an assault tank of the war – one which approached the enemy from under water.
Sir Albert Stern photographed in 1945. Source: National Portrait Gallery
Background
On 30th July 1940, Mr. Burton, the Director General of Tank Technology (D.G.T.T.), approached Sir Albert Stern to request S.V.D.C. assistance in solving two tank design questions: a tank suitable for an airborne invasion, and a tank for a seaborne invasion.
General Pope, the Director of Armoured Fighting Vehicles (D.A.F.V.) had actually issued the original requirements for an amphibious tank back in March and clearly, the task was so difficult that the S.V.D.C.’s help was now being sought. This difficulty is hardly a surprise given the almost utter absence of any work on amphibious or wading of tanks in the preceding decades, asides from some like the Mk.V and VI Light Tanks, and of course the minuscule Vickers-Carden-Loyd Amphibian (A.4E12). All of these were vehicles which were barely bulletproof and utterly useless for any invasion of the French mainland with an opposed amphibious landing against a prepared enemy.
Vickers-Carden-Loyd Amphibious Tank (A.4E12). Source: Wikimedia Commons
This need for an amphibious tank was less obvious in March 1940, when it was ‘something we might want’, as opposed to a post-Dunkirk point when the British had been pushed off continental Europe. Any new attempt to bring a land war against Germany in France would guarantee the need for an amphibious landing and this would have to be led by tanks. The small problem was that virtually no work had been done on the subject and there was no suitable vehicle available.
“the War Office considers it very important that an amphibian tank should be developed to meet modern requirements… It seems to me that this is a problem that might well be studied by your Committee, and the scheme developed possibly up to the stage of making pilot models… the development of an amphibian tank of real use is a matter of great importance.”
Letter from Sir Albert Stern to Mr. Burton, dated 9th August 1940
On 9th August 1940, Stern wrote back to Mr. Burton agreeing that the S.V.D.C. would assist in the design of an amphibious tank and that they would need £100,000 for the production of a pilot model.
Sir Albert Stern Stern invited Mr. Burton and General Pope to meet directly with the SV.D.C. on 12th August to discuss the exact requirements for this amphibious tank. General Pope, however, was unable to attend but forwarded to them the requirements as document ‘Specification 1.A Amphibious Tank Operations’ with the clear goal “to land tanks on an open beach in the face of enemy resistance and to gain a bridgehead 3 to 5 miles [4.8 – 8.0 km] deep to cover the landing of other troops”, certainly no small requirement.
The S.V.D.C. were to be tasked with investigation of a design which could be launched 200 yards (183 m) from the beach and navigated to shore above or below water if necessary and both of those options came with advantages and disadvantages alike. There was even the possibility of considering “fitting the necessary tracks and armour to a boat with some sea going powers but limited cross country performance” although the obvious impracticalities of such an idea were as apparent then as they are now. The S.V.D.C.-designed amphibian would have to be designed, trialled, and approved, and built in large numbers to be available by 1st April 1941 – less than a year away!
Armor was not going to be ignored as it had on the very limited attempts at amphibious tank work beforehand. This vehicle would have to be proof against all enemy small arms fire, including armor piercing bullets at normal impact at all ranges as a minimum. Further, the front of the tank should be able to resist the German 37 mm gun at normal impact at 300 yards (274 m). Armament, as dictated by General Pope’s requirements, was not the 6 pdr. Stern had been looking at the venerable 2 pounder. This was obviously going to be a disappointment in terms of not getting the bigger gun mounted but was a logical move given the incredibly tight time constraints needed. Adoption of a known and proven gun meant a lot of savings in development time. Alongside this gun was to be a 7.92 mm Besa machine gun and both weapons were to be mounted in a turret. Interestingly, there is no mention at all of a hull-mounted weapon of any kind.
Crewed by 3 men, a commander, gunner, and a driver, the tank would have to be able to manage 8 – 10 mph (13 – 16 km/h) on land cross country and negotiate water (either above or below the waves) at 4 knots (7.4 km/h).
Dimensions of the tank would be somewhat dictated by the need to cross trenches and climb steps but these requirements were far below those set for the other TOG tanks back in September 1939. This time, the need was to cross a gap 5’ 6” (1.7 m) wide and a step just 3’ (0.9 m) high. The vehicle would only need a range of operation of 50 miles (80 km) but would have to be able to climb up wet, loose, shingle beaches and be “capable of operating under tropical and European conditions”. The inclusion of a No.11 wireless set (or equivalent) as well as an inter-troop radio set completed the needs identified by the Army for the tank.
By 19th August, just 10 days after receiving the order, the SVDC had finished their design whilst still working on TOG-1, a new hydraulic system for TOG-1A, and the new primary heavy tank TOG-2, amongst other work.
The SVDC surmised the amphibious tank into 3 key considerations. Firstly, it had to be ready for action the moment it got to the beach – there would be no time to shed buoyancy packs or screens. Secondly, it would have to be immune to enemy fire, including strafing or bombing by enemy aircraft during the water phase of the assault and be as light and small as possible. Thirdly, by making the vehicle as small as physically possible, the armor requirements would likewise be kept as small as was possible whilst still meeting the requirements for protection which had been set. When Stern released the SVDC designs of the tank, it was to be 18’ 9” (5.7 m) long and just 7’ 9” (2.4 m) wide with the hull an incredibly small 3’ (0.9 m) high.
Accounting for a ground clearance of just 15” (0.38 m), this would mean that the top of the hull would be a mere 51” (1.3 m) from the ground. The driver would likely have to be lying a little supine in order to fit. What this tight design would do was to keep the weight to just 14 tons (14.2 tonnes) (plus or minus 10 %) (12.6 to 15.4 tons / 12.8 to 15.6 tonnes). The design produced was a tank which was only slightly lighter than the 16-ton (16.3 tonnes) Valentine (Infantry Mk.III) tank which also mounted a 2 pounder gun and was a little shorter than this vehicle. It proved to be unsuitable for amphibious wading.
An alternative method of unloading tanks on shore shown here with a Valentine (Infantry Mk.III) was fine on a beach like here in Sierra Leone where no enemy awaited the vehicle. This method was obviously hopeless for an opposed landing. Source: Imperial War Museum
“war should not be handled in this way.”
Report of Interview between Sir Albert Stern and Herbert Morrison, dated 3rd September 1940
Work continued through 23rd August with General Pope still adamant on the need for an amphibious tank and it was one of three topics of discussion at a meeting held on 3rd September 1940 and also to discuss the growing rift between Sir Albert Stern and Mr. Hopkins, the Director of Naval Land Equipment (N.L.E.). The N.L.E. felt out of sorts that the S.V.D.C. had been tasked with designing a tank to operate at sea, when the sea was something they felt was in their domain.
Yet, at the same time, Mr. Hopkins was perfectly happy to be carrying on a programme of development of an enormous trench digger which took engines from the S.V.D.C.’s own projects, having no qualms about his Department developing a land-based vehicle.
It is hardly any wonder that efforts at a high level took place to keep Mr. Hopkins away from meetings where Sir Albert Stern was going to be present, likely to protect him from the critique of that hypocrisy which would be inevitable. The split in the relationship of the two was not helped by the decision by Mr. Burton in September to strip from the S.V.D.C. of the role (still officially unofficial) of design responsibility of the amphibious tank and hand it to Mr. Hopkins at the N.L.E. telling Stern to “give out advice” – an optimistic sentiment all things considered and a slap in the face of Stern and the S.V.D.C. who had completed their design. With the obviousness that Stern would not work like that, Mr. Burton did eventually relent and agreed that the N.L.E. and S.V.D.C. should work together on the design and produce a working model.
That issue, amongst others connected with the other TOG designs, only served to illustrate and prove Stern’s point to Mr. Morrison that there was a need for a separate body solely in charge of tank design. A point he omitted no chance to press for and would not get. S.V.D.C. work officially ceased on 10th September 1940, all work was to go to the N.L.E. instead although the N.L.E. did continue to use the expertise of Mr. Ricardo for his engine expertise for some time afterwards.
Under the Sea
Valentine Tank fitted with the Duplex Drive floatation system – a large screen to displace enough water to make it float. The vehicles using this system were vulnerable to overtopping by waves and the canvas could easily be perforated by enemy fire. The tank could not fire back with the screen deployed. Source: Divernet and BBC respectively
The biggest difference between this SVDC vehicle and preceding designs was going to be that this vehicle was not going to try and float, but drive on the sea floor instead. The logic for this decision was as simple as it may be initially counter intuitive. Whilst on the surface, on pontoons or with a screen (like a Straussler system), a tank would be visible to the enemy the entire time and unable to fire back. At the mercy of enemy gunnery, casualties could be inflicted even before they reached the beach, at which point the encumbrance of the floatation equipment would be a big problem. Indeed, in 1940 this had not yet been overcome with Straussler equipment, explosive removal of wading equipment and waterproofing compounds to seal the vehicle.
The 1940 solution for the SVDC was both unusual and innovative in that, whilst on the seafloor, the tank would be completely immune to enemy fire and be able to rise out of the water at the surf instantly ready to fire on the surprised enemy watching these poseidon-esque vehicles rising from the depths.
On the sea bed, the tracks would be able to engage with the sand and shale at a higher speed than on the surface without worrying about a rip tide or breakers. In fact, the SVDC estimated a sea floor speed of 6 knots and, at the same time, completely removed the complications of a propeller or the as-yet-to-be-designed steerable water jets from Messrs. William Foster and Co. As the vehicle was in contact with a tractable surface (sand and shale of the beach) there were no worries about the vehicle becoming trapped in the surf onshore, as could easily happen with a floating tank with little purchase on the beach at this key point. A large vulnerable floating target therefore stranded on the foreshore like a whale could be avoided by just being underwater could the equal risk of becoming damaged on the way to shore with a pontoon becoming holes and the tank capsizing or sinking.
The obvious question over an underwater vehicle is the problem of keeping water out, however this is not as big of a problem as may be imagined. With a submersion duration of just 3 minutes, a small bilge pump capable of pumping 30 gallons (136 litres) per minute against a head of 25 ft. (7.6 m) of water was more than adequate for the task. The next obvious problem is air for the crew and engine. For the engine, this was provided for with tanks of compressed air and for the crew by simply battening down the hatches to prevent air escaping. There was plenty of breathable air inside the volume of the hull and turret for the time submerged. It is not that there was no time for escape either. Designed for submarines, the Davis Escape Apparatus was already available in 1939 and, by 1944, the Tank Underwater Escape Breathing Apparatus would also be widely available. That piece of kit provided up to 7 minutes of oxygen for each crew man to get to the surface of the water in case of a problem requiring escape.
Navigation underway was to be aided by means of a spot lamp on the turret and a compass, although it was accepted that submerged rocks might be a problem for which there was no easy solution, although most of the large ones had already been well charted.
Deployment
In order to protect the vehicle during the water phase of the assault, Sir Albert Stern, a man who was himself an amateur sailor with some experience in boats, proposed the use of a large ship to deliver the tanks. That ship would have to have a draft of at least 18 to 20 feet (5.5 – 6.1 m) and launch the tanks into water about 25 feet (7.6 m) deep via a ramp. As many tanks as possible should be packed onto that ship to maximise the weight of tank-force being delivered to the shore and this, with the ship size, meant deploying up to 600 yards (549 m) from shore instead of 200 yards (183 m).
In an October 1940 report, Mr. Ricardo suggested a suitable ship as a repurposed whaling vessel about 10,000 to 20,000 tons (10,160 to 20,320 tonnes) in weight, as they had ramps capable of dealing with whales weighing 80 to 100 tons (81 to 102 tonnes) and could launch “several hundred small submersible tanks” very quickly.
Armor
The TOG amphibian had to be proof against all enemy small arms fire including armor piercing bullets at normal impact at all ranges as a minimum. In addition to this, the vehicle should ideally be able to resist the German 37 mm gun at 300 yards (274 m) at normal impact although absolute immunity was accepted as unattainable for the tank.
To meet these needs, the first step was to make the tank as small as possible so as to present the minimum possible target to the enemy.
On top of that, armor not less than 2 ½” (63.5 mm) was proposed on the front, although 2” (50.8 mm) would probably be sufficient if needs be, especially where normal impact was unlikely. Side armor was to be substantially thinner, just ⅞” (22.2 mm) thick and with floor and roof plates between 3/8” and ½” (9.5 to 12.7 mm) thick.
Automotive
The primary manufacturer for pilot models for the S.V.D.C. was Messrs. William Foster and Co. of Lincoln and they had no experience in building amphibious vehicles. They did, however, have experience building barges for the Admiralty. Those barges were specifically designed to obviate the need for propellers for propulsion, as a propeller would be damaged by hitting a beach. The same sort of thing was going to be true of this tank design and the solution offered was to be the same too. If the tank was going to float, it would use jet propulsion instead of a propeller, even though the lack of a keel made those barges hard to steer and this would be the case with a floating tank too. The solution was to create a new design of a steerable jet instead.
Ground clearance was to be 15” (0.38 m) and the tank would run on tracks 18” wide producing a ground pressure of just 6 lbs. sq. in. (41.4 kPa). This very low ground pressure would assist in the obviously saturated ground it would have to drive on under the water but the bigger problem of being underwater was buoyancy.
Buoyancy was obviously essential if you wanted to float but here the important part was to not be buoyant. Floating was to be avoided and buoyancy was a function of the mass of water displaced. This tank was to weigh 14 tons (14.2 tonnes) so, if it displaced more than 14 tons (14.2 tonnes / 14.2 m3) of water, it would float.
The S.V.D.C. calculated the actual buoyancy of the tank as just 8.5 tons (8.6 tonnes), meaning that the effective weight of the tank when submerged was just 5.5 tons (5.6 tonnes) reducing the ground pressure to an incredible 2.5 lbs.sq.in. (17.2 kPa). Bearing in mind an average human exerts a pressure of about 8 lbs.sq.in. (55.2 kPa) reducing this to just 2.5 lbs.sq.in. (17.2 kPa) was exceptional.
A lesser-appreciated problem of running a vehicle underwater is that of engine cooling. With the engine compartment having to be sealed off during transit, the radiators would be out of action and this meant that the cooling would have to be able to work with a high water temperature, something which ruled out the possibility of simply cooling the engine with sea water.
This issue was resolved by use of a heat exchanger arranged in series with the radiator so that a fresh water cooling system could be retained, which could be the primary cooling on land. When submerged, the air intake shutters could be closed to keep sea water out and have the heat exchanger dump the engine heat to the external sea water. Even less of a problem was the exhausting of gases from the engine. Even against a head of 20 ft. (6.1 m) of water, the engine exhaust could comfortably bubble out the gas, although this would cause large bubbles on the surface of the water (the bubbles will expand on their way to the surface courtesy of Boyle’s law). If complete secrecy was needed, then these bubbles bursting out on the surface of the water could be disguised by means of a simple canvas pipe from the exhaust pipe of the tank to the small float on the surface. As soon as the tank surfaced on the beach, the canvas tube would drag behind and rapidly burn off from the heat, removing the need for someone to get out to take it off.
Air for the engine was to be provided for by one of two possible solutions. The first was the use of a 3” (76.2 mm) diameter telescopic tube to the surface of the water, but this was vulnerable to damage. The alternative, and the solution which was selected, was provided for by means of compressed air. It was calculated that the effort of driving the tank in the water-medium instead of air would waste 50 hp of the engine, so that 5 knots was the realistic submerged speed. At that speed, it would take 3 minutes to reach fresh air and, with the engines consuming around 1.3 cu. ft. (3.68 x 10-3 m3) of air per hp. per minute, a 3 minute journey would require 200 cu. ft. (5.66 m3) of air. In order to allow a margin of safety, two 400 cu.ft (11.3 m3) cylinders would be fitted, providing a 4:1 safety factor. With the engine power wastage through water and at the sprocket (an additional waste of 0.5 hp per ton per mph) and with a mechanical transmission efficiency of around 80%, the minimum engine size of 70% in an ideal world would actually would have to be 87.5 hp, which led the S.V.D.C. to decide an engine of not less than 90 hp was needed.
In considering an engine, there were two options. The first was a Ford V8, and the second was an engine from Vauxhall Motors, as used in the Bedford lorry. Both could produce the 90 hp required from 67 octane petrol but would also consume more air than previously planned for, specifically around 350 cu. ft (9.9 m3) of air for that 3 minutes of submerged driving. The adoption of the two 400 cu. ft. (11.3 m3) air tanks would still be sufficient and reduced the margin of safety from 4:1 to just 2.25:1.
Of the two engines, the Ford V8 was shorter, so this was chosen as the preferred motor.
Armament
At the time of the instigation of the TOG Amphibian programme in July 1940, the primary British tank gun was still the 2 pounder. A gun of 40 mm calibre, the 2 pounder was an excellent weapon capable of knocking holes very effectively through the armor of even the heaviest German tanks of the day. It was, however, seen by General Pope as having had its day. There was another gun on the drawing board for tanks and that was a 6 pounder gun. Not the low velocity 6 pounder of WW1 era tanks, but a new gun firing an armor piercing capped (APC) round as well as a usefully large high-explosive round. The old 2 pounder did have a high-explosive shell for it but it saw little service due to the very small charge it carried.
The Army, however, at this time, had at best an ambivalence towards this new gun, due in no small part no doubt to the lack of any tank able to carry it at the time.
The only design, in fact, for which the 6 pounder had even been tried on by this time was the A.12 and that project had ended that month, leaving Sir Albert Stern and the SVDC as the only people interested in it.
Sir Albert Stern was pressing the case hard at this time for adoption of the 6 pounder, in part for TOG-2 but also because he, like General Pope, clearly saw the need for a bigger gun than the 2 pounder for tanks. When Mr. Burton approached him that month then, it would have been no surprise at all if the 6 pounder formed the basis of the armament for both the airborne and amphibian designs the S.V.D.C. considered. Other than a note of the gun for the airborne vehicle, however, it was not to be. General Pope’s requirements were clear and called for a 2 pounder gun instead, and a 2 pounder gun it would have to be.
The gun had been chosen for them but the turret and diameter had not. Stern proposed the adoption of a turret with a diameter of 4’ 6” (54” / 1,372 mm), which would be armored to match the hull, producing a turret around 3.75 tons (3.81 tonnes) in weight when fully armed. This turret ring was slightly smaller than that used on the A.12 Matilda (54.3” / 1,379 mm) and A.22 (54.25” / 1,378 mm) but was exactly the same size as the turret diameter for the Cruiser Mk.III and IV (A.13). This is suggestive that it was to be an A.13 turret which would have been used, although it would have to have been uparmored to meet the frontal armor requirement.
When the N.L.E. did finally get around to producing an amphibian tank like this AT.1*,it was more boat than tank and a gargantuan target when on land. Despite decent armor protection, like the S.V.D.C. amphibian, these vehicles were bigger and heavier. The only thing they shared with the S.V.D.C. amphibian was that these also never entered production.
Conclusion
When the N.L.E. did finally finish their own amphibian tank designs in December 1940, they were nothing like the design from the S.V.D.C. Gone was any notion of being underwater. The N.L.E. machines would float. The N.L.E. continued to use the expertise of Mr. Ricardo even after 10th September 1940 and he revealed his views of their alternatives that October. In his report, Mr. Ricardo still emphasized the importance of a secret and safe underwater approach, still pushed for the S.V.D.C. design, and bemoaned the idea of a small floating tank. If a floating assault tank was to be used it should, he argued, be substantially larger and better armed. Mr. Ricardo felt that Mr. Hopkins made far too much of the water-elements of an amphibian tank considering it was only going to be in the water for a few minutes. Further, Mr. Ricardo set-aside much of Mr. Hopkins’ objections especially when it came to the engine stalling underwater and he was on good ground to do so – Mr. Ricardo had, after all, extensive experience dealing with engines for submarines. The result was that no S.V.D.C. Amphibian tank was ever built and for that matter, the British never fielded a dedicated amphibious tank at all during the war.
David Bocquelet’s possible rendition of the TOG amphibian
TOG Amphibian Specifications
Dimensions (LxWxH)
18’ 9” (5.7 m) x 7’ 9” (2.4 m) x 4’ 3” (1.3 m), ground clearance 15” (0.38 m)
Total weight, battle ready
14 tons (14.2 tonnes) (plus or minus 10 %) (12.6 to 15.4 tons / 12.8 to 15.6 tonnes)
Crew
3, commander, gunner, and driver
Propulsion
Ford V8 90 hp petrol or Vauxhall 90 hp petrol
Speed
8 – 10 mph (12.9 – 16.1 km) on land cross country and negotiate water (either above or below the waves) at 4 knots (7.4 kph)
Range (road)
50 miles (80.5 km)
Trench Crossing
5’ 6” (1.7 m)
Step
3’(0.9 m)
Armament
2 pounder gun and 7.92 mm Besa in turret
Armor
Proof against any small arms AP fire at any range. Proof against 37 mm AT fire at 300 yards (ideal) at 90 degrees.
Front: 2 ½” (63.5 mm) thick, if needs be down to 2” (50.8 mm) thick where normal shell impact was unlikely.
Sides: ⅞” (22.2 mm) thick
Floor and roof: 3’8” to ½” (9.5 to 12.7 mm) thick
Radio
No.11 wireless set (or equivalent) as well as an inter-troop radio set
Sources
Hills, A. (2017). The Tanks of TOG: The work, design and tanks of the special Vehicle Development Committee 1939-1945. FWD Publishing, USA
Hills, A. (~2021). Striding Ashore. The History of British Tank and Armoured Fighting Vehicle Amphibious Wading Development in World War II. FWD Publishing, USA
Letter from Sir Albert Stern to Mr. Burton, dated 9th August 1940
Report of Interview between Sir Albert Stern and Herbert Morrison, dated 3rd September 1940
Notes made by Chairman; Visit to Lincoln 14th and 15th August, by Sir Albert Stern
Letter from G. D. Burton to Sir Albert Stern, dated 12th August 1940
Secret note entitled ‘Amphibious Tank Operations’ 1A, undated
Recommendation from Sir Albert Stern for an Amphibious Tank, dated 19th August 1940
Memorandum by Mr. Ricardo on the subject of the ‘Amphibious Tank,’ dated 21st October 1940
War Office Training Film: The D.D. Amphibious Tank: Sherman III D.D., Mark II
This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Cookie settingsACCEPT
Privacy & Cookies Policy
Privacy Overview
This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may have an effect on your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
United Kingdom (1942-1943)
