United Kingdom (1943)

Infantry Tank – 1 Prototype

The A38 Infantry Tank, codenamed as ‘Valiant’. Much has been said about this widely maligned British tank design, perhaps too much when one stops to look at the vehicle and its very short lived story. Reports of unsettling injuries to crewmen, horrendous shot traps, and poor comparison to existing infantry tanks to name but a few. However, how much truth really exists behind these statements?



Tank, Infantry, A38 Valiant, a Misunderstood Failure. Photo: Osprey Publishing

‘An Urgent Project’

Development of A38 Infantry/Assault Tank started in August of 1942, when Vickers Armstrong were awarded a contract to produce three pilot models of a ‘heavy assault tank’ by the Ministry of Supply. This had followed discussions from the Tank Board of improvements and possible successors to the Valentine Infantry Tank series. This design was classed as ‘urgent’ by the Tank Board and would be focused on along with improvements to the existing Valentine series. There was also a specific emphasis placed on the implementation of side skirting plates in this design. However, the design of the Valiant had origins in an existing project by Vickers; the Vanguard.

Vanguard was an existing design that had been presented and designed earlier by Vickers as a possible replacement for early infantry tanks such as the A11 Matilda I and early models of the Valentine. The design was interesting in that it utilized a unique suspension system, sharing some commonality in smaller components with the Valentine. The system consisted of independently sprung pairs of road wheels, each supported by external wishbones. This chassis had been used in the first trials of the QF 17 pounder AT gun in what would eventually become the Archer SPG, which was a 17-pdr mounted to a rear-facing Valentine chassis. With this design already drawn up and built, Vickers simply designed the new tank on top of this existing object.

The original design for the assault tank, which continued to be referred to as ‘Vanguard’ for at least the few months of its development, was very similar to the final vehicle that was built. The weight of the vehicle was 23 tons, as required by the contract, making it a much lighter alternative to the A33 “Excelsior” and A22 Churchill tanks that were in development at the same time. This reduced weight was achieved by reducing the turret from a 3-man configuration to a 2-man configuration.



The design drawing for the A38 Valiant. Photo: The Tank Museum Archives

The design was armed with the proven 6 Pounder (57mm) gun, with a 7.92mm BESA machine gun mounted coaxially. The 6pdr was a preferred weapon to the more commonly available 2 pounder (40mm) due to its wider range of ammunition and ability to perform outside of an anti-tank role. Two 2 inch (51mm) smoke mortars were to be included, with 18 smoke bombs being provided. Frontal hull armor was listed at 4 ½ inches (114mm) thick, with the sides having 4 inches (102mm) and the rear 3 inches (76mm). This gave the vehicle very impressive protection for the time, especially in comparison with early war designs such as A.11. The design also featured a pike nose design, utilising two plates that were ‘pre-angled’ to give greater armor obliquity angles. This shows a level of forward-thinking that would not be seen on a tank until the reveal of the Soviet IS-3 heavy tank in 1945. The turret was a small design, bearing in mind that it was meant only to accommodate 2 crewmen. It bore a resemblance to the Valentine MK. X turret, however, its design had some variance in features. It featured a large single door hatch in the left side, as to allow for a quick escape in the case of the tank being knocked out, as well as allowing for easier loading of the proposed 55 rounds of 6pdr ammunition to be carried. The top of the turret featured a single split-door hatch for the commander, as well as two periscopes for vision under closed-down position and two antenna mounts.



The original wooden mock-up of the A38 Valiant. Photo: The Tank Museum Archives

Mobility was listed at 16 mph (25.75 km/h), made possible by the Rolls-Royce Meteorite; a proposed 8-cylinder engine capable of 400 horsepower. The road range, or ‘circuit of action’ as described by the design specification, was 100 miles (161km). The design was to have a 30-degree minimum climb angle, as well as the ability to clear a 3 inch (76mm) obstacle. Steering was to be conducted in the traditional ‘clutch and brake’ configuration. The design was specified with a 5-speed synchromesh gearbox. Interestingly, later in the development of Valiant, The Department of Tank Design conducted a report on the amount of effort required in gear changing with Valiant, Valentine and the M4 Sherman. It was found that little difficulty would be experienced with Valiant, except for some difficulty when changing from second to third; this was suggested to be improved by fitting a diesel or ‘oil’ engine which would enable the engine to pick up at lower speeds. The suspension was of the aforementioned ‘Vanguard’ type. This consisted of six pairs of road wheels per side. These pairs of rubber-tired road wheels are mounted onto independent transverse spring units, each supported by an internal spring and a wishbone mount. Shock absorbers in the form of 8 hydraulic double piston stations are present on wheel stations 1, 2, 5 and 6. There are 3 top rollers provided to support the upper weight and tension of the track. The track itself was specified as 20 inches (50cm) wide and of manganese construction. Featuring twin guide horns, these tracks were specified to produce 10.5lb./sq.in. (7g/sq.cm) of ground pressure.

This initial design can be compared favorably to existing tanks that were in production, considering that these were designed in the late 1930s. The armament was superior to that on previous infantry tanks such as A11 and A12, as well as early models of Valentine. This gun not only allowed it to be effective at engaging enemy armor, but also allowed it to perform its primary function of infantry support, something that existing British guns in the form of the 2 Pounder were not capable of. The armor profile was designed fairly ahead of its time with the use of slopes and pike noses, no major shot traps existed on this original vehicle.

From Vickers to Rolls-Royce, Rolls-Royce to Ruston and Hornsby

The vehicle continued to be developed at Vickers for a few months after the contract had been awarded, with amendments regarding engine power. The contract now called for six pilots, four to be designated as Mk.I using existing engines found on the Valentine series; these were the A.E.C produced A189 petrol engine and the General Motors Company produced diesel engine, producing 135 and 138 horsepower respectively. The remaining two pilots were Mk.II, equipped with the originally specified Meteorite by Rolls-Royce or an unspecified V8 petrol engine produced by Ford. Due to poor reception of the 6pdr in the Valentine IX, the Tank Board suggested in February of 1943 that a 75mm armament was worked into the design of the tank, however, this was never implemented. A 3-man turret was also specified. Shortly following these changes, Vickers decided that the project was to receive a new parent designer. The reason for this was stated as a response to increased workload and a priority shift at the Chertsey facility; the project had already been declared as of lower priority by the Tank Board, stating that the bulk of Vickers’ workload was to focus on the continuation of existing tank production, as well as building American tanks. The new parentage of the design was undecided at the time, however, it had been agreed that Rolls-Royce would be responsible for developing the engine and transmission compartment; this work would be completed at their facility at Belper (Derbyshire); the engineers here had previously worked on the A.33 Assault Tank design in 1941.

This is where the first design alterations were made from the original Vickers design. The exhaust openings were moved from facing the sides of the vehicle to the engine deck, where they now faced upwards. Along with this, the transmission housings were up-armored. This was done by welding several large plates below the transmission. These alterations were the first that began to have negative impacts upon the Valiant, as it added an imbalance of weight towards the rear suspension. The original ground clearance of the design was 16.9 inches (43cm), an average value in comparison to tanks of the time. However, 4 ½ inches of armor plate reduced this value not only with the physical thickness of the material, but also by weighing down the rear suspension and causing the whole vehicle to sink to the rear. By the time the ground clearance data had been taken in May of 1945, the suspension gave an eye-watering 10 inches (25cm) of ground clearance at the rear and 8.9 inches (27cm) from the rear suspension units. By May of 1945, the suspension had been in existence for a few years and had been the basis of the Valiant prototype since 1944, giving a year for these additions, as well as the engine to drop the ground clearance. Thus, it can be assumed that the ground clearance was perhaps greater upon the completion of the prototype than in its suspension trials.



The rear transmission armor. Note the downward drop in suspension caused by the additional plate of armor. Photo: Author’s own

Two months following the decision to transfer responsibility to Rolls-Royce, the Ministry of Supply named a new parent for the project, now known as A.38 Valiant, as Ruston and Hornsby (R&H), and terminated the existing contract with Vickers Armstrong. Ruston and Hornsby had experience in building diesel and steam locomotives, as well as producing A.12 Matilda II. However, they had no prior experience in designing armored vehicles. R&H made several amendments to the design. The front armor profile was altered, whilst the pike nose was retained, a new superstructure was added to the front, creating a large bulge which not only added weight to the design, but also created a massive weak spot in the armor. The new 3-man turret was also designed at this stage. To accommodate the larger turret, the turret ring was increased by welding two elliptical plates to either side of the hull, further increasing weight. The new turret itself was much larger than the original turret, with a central bulge that presented a severe shot trap. The turret ring itself was unarmoured, causing further vulnerability to it being damaged by enemy fire.



The altered front profile. Note the retention of the pike front underneath. Photo: Author’s own



One of the added turret ellipticals. Photo: Author’s own



The air intake vents, moved upwards by R&H. Photo: Author’s own)



The final turret design. Photo: Author’s own

A38 Valiant specifications Dimensions 5.4 x 2.8 x 2.1 m (17 ft 8.6 in x 9 ft 2 in x 6 ft 10.7 in) Total weight, battle ready 27 tons Crew 4 (driver, commander, gunner, loader) Propulsion GMC 6004 diesel 210 hp (157 kW) 7,8 hp/t Suspension Individual coil springs, double-wishbone Speed (road) 19 km/h (12 mph) Range 130 km (80 miles) Armament QF 6 pdr (57 mm) gun, coaxial Besa 7.92 mm, 2-in smoke bomb launcher Armor 34 to 114 mm (1.3 to 4.5 in) Total production 1 in 1944

Sources

Special thanks to Ed Francis for his personal assistance and his discovery of the information on Vanguard that assisted in this piece.

Archives of The Tank Museum, Bovington, UK.

Examination of the A38 by the author, Bovington Tank Museum



Illustration of the A38 Valiant by Tank Encyclopedia’s own David Bocquelet, with corrections from Alexe Pavel.

‘Heavy Valiant’

The ‘Heavy Valiant’ was a separate design to Valiant that appeared in February of 1944, presented to the Tank Board by Rolls-Royce. It is not a ‘Valiant Mk.III’, nor is it a development of Valiant Mk.II. It is also a completely different machine from the A.33, also known as ‘Excelsior’ or ‘Heavy Cromwell’, although it was to use several components from this vehicle. The purpose of this design was to produce an ‘assault tank with exceptional protection’, as stated by the design brochure, specifically to have 50% greater armor than on any current British or American design. The intent was to produce a vehicle that could reach these requirements by compressing internal volume and reducing the crew number to 3, which would solve the problems of increased weight and dimensions. From the design brochure, it seems that this vehicle was pitched as an improvement on the A33 Excelsior, which had been designed previously by Rolls-Royce at Belper.



The initial plan for ‘Heavy Valiant’. The HVSS suspension system from T1/A.33 is clearly visible. Photo: The Tank Museum Archives

Upon viewing the design for Heavy Valiant, many visual similarities are shared from the Valiant, albeit in its final form. Dimensions were 20 feet 10 inches (6.3m) long with the armament forward and 10 feet 4 inches (3.1m) wide, larger than Valiant Mk.I, but smaller than the A33 Excelsior, which had the problem of being unable to cross the standard Bailey Bridge used by the British Army. The pike nose was present, with a frontal thickness of 9 inches (220mm) on the frontal upper plate and 8 ½ inches (210mm) on the lower plate. Side armor was listed 5 ½ inches (140mm), along with additional skirting that covered much of the suspension. The final weight of the vehicle was 42.27 tons (38.34 tonnes), making it more than twice the weight of the original specification of what became Valiant. The thickness of the belly plate was 25mm thick, a 5mm increase from that on the A33. The turret of the Heavy Valiant was almost identical in shape and design to that on A.38 Valiant, however, the frontal thickness of the casting is a staggering 10 inches thick, with an armored recess for the turret ring to prevent it from being damaged in combat.



The armor profiling of ‘Heavy Valiant’. Note the retained pike nose of the A.38 Photo: The Tank Museum Archives

The armament on the Heavy Valiant was varied. The main armament was a selection of 3 guns; the American 75mm as used in the T1 Heavy, the 6-pdr as used in the existing Valiant design, or the 95mm howitzer, a gun most famously used on the A27L Centaur in a close support role. This armament was to be accompanied by a 7.92mm BESA machine gun in a coaxial mounting, as well as one 2 inch smoke mortar. Alternatively, .303 machine guns and even the 20mm Oerlikon cannon were suggested for ‘increased man-killing proposition’. As an infantry support vehicle, the design states reliance on special ammunition types such as sabot, hollow charge and squeeze bore to increase penetration in case the vehicle is required to destroy other armored targets, highlighting the emphasis of this vehicle not being primarily intended to engage other tanks.

The maximum speed of the vehicle was to be 13 mph (20.92 km/h), slower than originally envisioned with the Valiant’s speed of 16 mph, however, given the increase in weight the difference is quite small. The engine was to be the same Meteorite V8 engine as on the Valiant Mk.II, tuned to 330 bhp. The road range was to be 60 miles (90.56 km), provided with a full tank of 63 gallons of petrol fuel, a reduced range from Valiant. The transmission was a 5-speed Rolls-Royce synchromesh gearbox, with a 16 inch (41cm) triple plate clutch. Steering was to be conducted through an epicyclically controlled unit built by Rolls-Royce. The suspension was a Horizontal Volute Spring Suspension (HVSS), the same used on the T1 Heavy Tank design from the U.S.A; this was carried over from the A.33 also, a possible reason as to why these two designs are sometimes mistaken as the same. The suspension had 3 units per side, each carrying two pairs of rubber-tired road wheels. The track system was also carried over from the T1/A.33, this was a 25 ½ inch (65cm) wide track with rubber insert pads. Both of these units had already completed 1000 miles of testing from A.33, so they were seen to have been proven. Suitable mobility was a primary focus for this design, as it was seen as a part of the vehicle’s offensive capability. Additionally, the design utilized the same turret traverse gear as the A.33 Excelsior. The power to weight ratio of 8hp per ton was not appreciably worse than that of the A.22 Churchill, which was in service at the time.

As a design concept, the Heavy Valiant was a significant improvement over both the A38 Valiant and A33 Excelsior designs that had preceded it; understandable given the time gap between the designs. The Heavy Valiant would have been a more suitable vehicle for 1944, with its heavy armor and proven infantry support armaments. However, the design did not get past design stages, with rumors of a prototype being completed and sent for trials at Lulworth (the British Army Armoured Fighting Vehicle Gunnery School located in Dorset) being unproven at best; no reliable sources pinpoint this occurring at all. This fate was shared with many similar designs for heavier vehicles such as A43 Black Prince or the A39 Tortoise. All of these designs came at a time when the ‘Universal Tank’ concept had been introduced, a concept that eventually culminated in the Centurion.

The Suspension Trial

The suspension trials for Valiant have probably become the most well-known stage of the vehicles development cycle, with good reason. These trials are well known for the sheer amount of problems that were encountered by the testing team. However, it is important to be aware of the fact that these trials were for the suspension only; the trials took place in May of 1945, after the end of the war in Europe. Due to the Tank Board’s decisions to press on with continued production and development of existing vehicles such as the A22 Churchill, as well as contemporary designs such as A43 Black Prince that mounted more capable armaments, the Valiant became an extremely low priority, with only a single prototype of a Mk.I having been completed by R&H in early 1944, by which time it was essentially obsolete. On these grounds, serial production of the Valiant had not been entertained since the first half of 1943. However, the Vanguard suspension system was seen to be ‘novel’ on a heavy vehicle and thus worthy of further trials; the previous trials had only occurred on lighter SPG mounts for the 17-pdr.



A view of the Vanguard suspension system. Photo: Author’s own

The Valiant was delivered to the Fighting Vehicle Proving Establishment at Chertsey, Surrey, on 7th May 1945; this was the primary facility for the proving and trials of armoured fighting vehicles at the time. The vehicle was the sole produced prototype; the proposed 3 vehicles were never built and never equipped as Mk.II tanks with Ford or Meteorite engines. The prototype was weighed at 27 tons (24 tonnes); the additions made by R&H, as well as Rolls-Royce at Belper had added 4 tons (3.6 tonnes) to the specified weight of the design.

The first action conducted by the test team was a measurement of the vehicle’s unladen weight; without crew or ammunition loaded, but filled with fuel, water and oil. The result of this was 26 tons and 13 hundredweights (27.1 tonnes). The next stage was the measurement of ground clearances. This was the first major fault that the test team recorded; the ground clearance was found to be unacceptably low. With the ground clearance at the rear at 9.6 inches (24cm) and rear suspension clearance at 8.9 inches (22cm), the vehicle would have had great difficulty on uneven terrain, with a high possibility of suffering suspension bolt shearing and being susceptible to high centers. The results, however, also record the hull ground clearances at 17.45 inches (44cm) for the front and 14.1 inches (36cm) for the rear. This would indicate the sinking of the vehicle suspension to the rear, where Belper and R&H made alterations to the transmission armor. This is also a feature that can be seen to those who visit Valiant in the Tank Museum today.

The next part of the trials involved a road test on cross-country terrain, conducted to establish the general quality of the ride, as well as the suitability of the suspension system for cross-country operation. Pitch tests were to be conducted as a part of the run, however, these trials were not conducted as the vehicle was unable to reach the cross-country trail. The vehicle was run on road conditions for approximately 13 miles (21km), during which several observations were made. Firstly, the engine oil tank had been overfilled, which was causing the oil breather to spit oil and thus cause the test team to suspect an oil leak. The reason for the overfilling was determined due to the lack of a measuring stick with the vehicle. The steering tillers of the vehicle were found to be excessively heavy; the driver was unable to continue due to fatigue. After the trials, the vehicle was placed in the workshops to determine whether this was a fault of the design or due to improper adjustment of the tillers; the heaviness of the clutches used for the steering was found to be responsible.

The footbrake also required assistance from the steering tillers, as to disengage the steering clutches before braking could occur. Furthermore, the footbrake placement in the hull necessitated the use of the heel to use it. During operation, it was speculated that there was a risk for the driver of having his heel trapped between the footbrake and the floorplate, causing ‘serious injury’. Contrary to a commonly held belief, there is no mention of a foot amputation risk on this vehicle, at least not on the official trial report. It was found that there was so little space between the gear lever in the 5th position and the right steering level, there was a risk of the driver’s wrist being broken by the violent action of moving the gear lever. The 1st gear position was located behind the battery boxes of the vehicle, where it was found to be extremely difficult to engage and physically impossible to disengage without the use of a lever or crowbar to assist. The driver’s position was also subject to criticism. It was noted that the driver had to occupy a crouched position, which presented to him a risk of serious injury from the hatch doors. The trial also pointed out the underpowered nature of the GMC engine that the tank was equipped with, noting that the vehicle encountered powertrain difficulties when dealing with even slight inclines. The suspension system, the main purpose of the trials, was found to have exposed lubrication points; the grease nipples. These grease nipples were quite fragile and would have been liable to destruction by cross-country terrain.

There were also some major letdowns in terms of maintenance. The vehicle did not include a level plug for the right-hand final drive, making any final drive servicing impossible. The final observation made by the team was the process for checking the gearbox levels and adjusting the steering brakes. Both of these necessitated the removal of the rear access louvers; these are extremely heavy on this vehicle. The procedure would require three men and a considerable amount of time to complete. At 13 miles (21km), the team decided that the vehicle was unsafe for continued operation and thus had the vehicle recovered and towed back 13 miles (21km) to the FVPE. After this, the vehicle underwent some extensive mechanical investigations in the workshops on the site, as to determine the causes of some of the technical faults found earlier.



A closer view of the exposed lubrication lines. Photo: Gabe Farrell

The trial report made several conclusions. Firstly, it was noted that the basic design of the vehicle was at fault in so many respects that there would be no useful purpose in its continued development or trials. A major concern made in the report was also that the vehicle was entirely unsafe to be put on the road and would present a danger to other road users. These limitations, as well as the technical limitations of the suspension, were seen to render any favourable points of the wishbone suspension system as “utterly valueless”. Due to the vehicle being undrivable beyond 13 miles (21km), the team stated that it would be unfair to expect anyone to risk the injuries that are presented to the driver. A final conclusion was that the design would require sufficient modifications to be introduced to make the design driveable and reasonably safe, with no mention of the further modifications that would be required to produce a serviceable vehicle.

With these conclusions, the FVPE recommended that the vehicle be immediately withdrawn from the suspension trials and returned to its makers at R&H. The report also suggested that the entire project be cancelled; a recommendation that was followed ultimately.

Conclusion: A Stinker or A Tragedy

At face value, this tank may indeed seem to be deserving of its moniker as the worst tank design in the history of AFVs, especially given the more dubious claims of the suspension trial regarding the risk of the driver losing his foot. Indeed, the final prototype suffered horrendous design traits and was outclassed in the time of 1943-1945. However, it must be remembered that the design was early war in nature; the suspension system was a pre-existing design and even the original Vanguard design was pre-1942. In this respect, the original design was actually very favourable and was an improvement on the infantry tanks that came before it, such as Valentine and A.11 Matilda, with innovative armour angling and an improved armament. Additionally, the original specification for a Meteorite engine would have made the vehicle far more reliable in terms of mobility. It is only after the vehicle is evaluated after the design alterations that it becomes more difficult to find praise. The additions made by Belper and R&H were responsible for increasing the weight of the vehicle, which had negative effects on the suspension system and overall mobility, as well as failing to implement the improved engine of the Mk.II. The wishbone system had proved itself as notable of further development from its performance on lighter SPG trials, the problem was its use on a vehicle that was 19 tons heavier than on these trials.

After the trials had seen the prototype be rejected, it was decided that it would be retained by the School of Tank Technology for educational purposes. While at the school, students were often invited to point out as many flaws as they could with the design; even as a failure, the design seems to have served some purpose in this regard. During the 1950’s, the vehicle was withdrawn by the Ministry of Supply and added to the collection books of the RAC Tank Museum in Bovington. Whilst here, it spent time indoors, as well as outside in the car park, before finally being kept inside the World War Two hall, where it can be observed today, alongside other British design oddities.



The A38 Valiant as it sits today in the Bovington Tank Museum. Photo: Author’s own.