Friday 15 January 2016

Britain's Christie

In the mid-1930s, the British military split up its tank into three classes. Light tanks retained their status, their goal was reconnaissance. A new class of infantry tanks had thick armour and low speed, and was called upon to escort infantry. Medium tanks were reclassified into cavalry (cruiser) tanks, whose job was to quickly move through the battlefield and perform raids through the enemy's rear. They were also tasked with fighting enemy tanks. To complete this task, they had to have high speed and powerful armament. The first fully fledged cruiser tank was the Cruiser Tank Mk.III.

Catching up to the Soviets

The early 1930s were a time of crisis for British tank building. The only tanks accepted into the army at this time were light tanks. As a result, these tanks were the core of the British armoured forces.

There was nothing to be proud of here. 4-5 ton tanks armed with a heavy machinegun at best were completely unsuitable for combat in Europe. As for medium tanks, they stagnated. The acceptance of the A7 Medium Tank that has been in development since 1929 did not lead to anything good. The first representative of the cruiser class was the A9, also known as Cruiser Tank Mk.I, developed by Vickers. This vehicle had a massive amount of problems, especially with reliability.

The cruiser class did not come from nothing. In 1936, during fall exercises of the Kiev Military District, Lieutenant-Colonel Gifford le Quesne Martel from the mechanization department of the Ministry of War was among the foreign observers. He was a notable figure in British tank building. For instance, the popularity of tankettes was his doing. He was very impressed by columns of Soviet convertible drive BT tanks. In his opinion, these tanks were the most suitable for modern war. The A7 tank was accepted into the army immediately after as the first cruiser tank, but it was obvious that this was a temporary measure. Another more maneuverable vehicle was needed.

Knowing that time moves quickly, the British engaged American tank designer John Walther Christie. Christie was not doing that well at the time. His tanks were passed over for production, and his ideas of flying tanks were only popular with the press, so the British proposal was accepted quickly. On October 3rd, 1936, an agreement was signed between the Wheel Track Layer Corporation and Morris Motor Company for the purchase of one tank. According to contract #89, 8000 Pounds Sterling were paid. The appearance of a new buyer caused such enthusiasm that Christie and his chief tester travelled to England along with their tank.

The tank that the British bought was very interesting in itself. Many authors, including Peter Chamberlain, claim that the M1932 flying tank was trialled, but the British actually tested a vehicle with a much more complex history, the M1931. This tank was the predecessor of the Christie T3 Medium Tank and the Christie T1 Combat Car. In June of 1932, Christie tried to sell it to the Bureau of Ordnance for $20,000. As trials of the vehicle resulted in a long list of defects that needed correcting, the deal fell through.

Christie left his tank in the courtyard of the Bureau of Ordnance building. A few months later, the tank was moved to storage, where it spent four years. After the British showed interest in Christie's tanks, the M1931 was quickly repaired and sent to England. The vehicle, indexed A13E1 with registration number T.2086, arrived with no turret. Documents listed it as a tractor. From fall 1936 to spring of 1937, the A13E1 underwent intense trials at a proving grounds near Aldershot, Hampshire county. In total, the tank travelled 1085 km, 523 of them off road. A turret was designed for the tank, and a model was made, but it was never built in metal.

Thanks to this new income, Christie created another flying tank, indexed M1937. This was more of a test chassis than a real tank, but this did not make it any less interesting. Unlike the A13E1, the M1937 was a fully tracked tank. Thanks to the Curtiss D-12 aircraft engine, with power reduced to 430 hp, the tank could go faster than the M1931 could on wheels. Aside from the candle spring, the suspension used a parallel shock absorber. This solution made the suspension significantly better, as it quickly reduced oscillations during acceleration and braking.

This new tank also interested the British. The M1937 crossed the Atlantic, and its trials began at the Farnborough airport. The tank achieved a maximum speed of 102.5 kph, which amazed the observers. However, Christie's dreams of selling the new tank and its patents were never fulfilled, as the requested sum of $320,000 was too great. Nevertheless, more money from the British allowed Christie to keep working on his flying tanks, sadly in futility.

English Method

In 1937, work started on the analogue to the Christie tank, indexed A13E2 Cruiser Tank. Engineers of the Morris Motor Company, turned into the multifaceted conglomerate Nuffield Mechanization & Aero in 1938, borrowed the suspension, engine, transmission, and cooling system from the Christie tank. Otherwise, the A13E2 was its own vehicle, significantly different from other tanks that descended from Christie's designs.

First, the British discarded the convertible drive. By the late 1930s, the lifespan of tracks surpassed 1000 km, and this took away one of the advantages of putting tanks on wheels. The maximum speed of this new tank was 50 kph, which was enough for a cruiser type tank.

Morris Motor Company engineers borrowed the idea of parallel shock absorbers from the M1937 tank. At the same time, they ignored another feature of the vehicle, slanted springs to reduce the height of the tank. In order to not overdo it with novelties, it was decided to leave the springs the same as they were on the M1931. The 12 cylinder V-shaped Liberty L-12 aircraft engine was left unchanged. The British set up domestic production, naming the new engine Nuffield-Liberty.

The design of the hull was radically changed. The Christie tank had a ram-like front, which increased the chances of ricochet at the cost of making installation of the idlers a pain. Breaking the idler axle was a common problem with these tanks. In addition, the hull of Christie's tanks was narrow, which limited the width of the turret ring.

British engineers designed a new hull that was half a meter longer and 10 cm wider than its American ancestor. The front of the hull retained a shape traditional for British tanks of the 1930s, similar to the A9E1 prototype. Installation of machinegun turrets was a trend at the time, but the A13E2 did not have any. The driver sat in the center in a special casemate that allowed him to have very good visibility. The rest of the hull was new as well, only the mufflers remained unchanged.

The tank received a large amount of hatches. This had a negative effect on the strength of the tank's armour, but it was only 14 mm thick, hardly enough to protect from even high caliber machinegun fire.

The turret had nothing in common with Christie's creations. Instead of a one-man turret that was already insufficient in 1932, engineers of the Morris Motor Company built a three-man one. Its design was similar to that of the A7 tank. Similar turrets were used on the Cruiser Tank Mk.I and Mk.II. The turret had a 40 mm 2-pounder gun and a Vickers machinegun, although the prototype only had mockups of the armament.

The A13E2 was ready by October 1937. Trials of the experimental vehicle, registration number T.2085, began that same month, and demonstrated the correctness of Martel's decision. The 14 ton vehicle with American roots could achieve a speed of 56 kph, almost reaching that of the 5 ton Light Tank Mk.VI.

However, there were some "growing pains". The tracks, which migrated from Christie's tank unchanged, caused some complaints. Their drawback was excessive wear of the tires. The result was a new tank, A13E3, registration number T.3642.

One of the novelties was a new small-linked track, which increased the lifespan of the road wheels. The maximum speed of the tank was limited to 48 kph. The A13E3 received real guns instead of mockups, which allowed for proper gunnery trials.

Arduous Pioneer

The A13E3 was accepted into service as Cruiser Tank Mk.III as a result of the trials. Nuffield Mechanization & Aero was tasked with its production, turning the company that dealt primarily with cars until the mid 1930s into one of the largest British tank makers. The company's tank branch only bloomed after the start of WWII, the order for tanks in 1938 was quite small. The British Ministry of War spent little on tanks compared to the Navy or Air Force.

The cost of British tanks is easy to estimate at the time: it ended up being about 1000 Pounds Sterling per ton, meaning that the 14 ton tank cost about 14,000 pounds. By the exchange rate of the time, this was about 150,000 Reichsmarks or 68,000 American dollars. To compare, the PzIII cost about 110,000 Reichsmarks and the Medium Tank M3 cost 55,000 dollars.

Production Cruiser Tank Mk.IIIs differed from the A13E3 slightly. The right side of the turret was equipped with a pair of smoke grenade launchers (mounts for them were were present since the A13E2) and the exhaust system was covered up.

The initial order for Mk.III tanks was only 65 units, registration numbers T.4385 through T.4449. The small volume of the order was due to an understanding that a tank with so little armour would not last long on the battlefield. Work started on an improved version, the Cruiser Tank Mk.IV. However, the successor didn't go much further in terms of armour.

Despite the Cruiser Tank Mk.III being a learning experience, it still saw combat. On September 1st, 1939, the British army only had 79 cruiser tanks of all types. Another 322 tanks were built before June of 1940, but it took time for these tanks to make it to the battlefield. As a result, when the Germans began their offensive through Belgium in May of 1940, the British sent everything they had to stop them. The British Expeditionary Force was equipped with 38 Cruiser Mk.III tanks, included into the 3rd and 5th Royal Tank Regiments, which in turn were a part of the 1st Heavy Tank Brigade of the 1st Tank Division. Later, the 3rd and 5th RTR were included in the 3rd Armoured Brigade.

The new tanks saw combat for the first time at Abbeville in late May of 1940. The effectiveness of the tanks was impacted by the fact that the 1st Tank Division commanded by Major-General Evans arrived in France only on May 15th, and several of the units were not entirely assembled. There were also other problems. The British tanks ran into the same problems as Soviet BT-2 and BT-5 tanks did: the Liberty engines were very picky, and tankers had to fight their own tanks as much as they did with the Germans.

The tank was fast, maneuverable, and had an excellent gun, but it was defenseless against German anti-tank guns. It can't be said that the Germans did not notice these new tanks at all, but they were unable to play a significant role in this battle. The tanks were last used to defend Dunkirk, and were abandoned there. The debut of the Cruiser Tank Mk.III was also the end of its combat career. There are rumours that some of these tanks were sent to North Africa, but they have not been confirmed.

Some tanks were recovered by the Germans in relatively decent condition. The tanks were indexed Kreuzer Panzerkampfwagen Mk.III 743(e), but there is no evidence that they were sent to either combat or training units. At the very least, one Kreuzer Panzerkampfwagen Mk.III 743(e) was sent to Kummersdorf for trials, where it was mobilized among other vehicles that the Germans sent into battle against the Red Army in April of 1945. The results of this desperate attempt were quite obvious.

Until recently, there were two preserved Cruiser Tanks Mk.III. One was in storage at the Atlantic Wall Museum in Pas-de-Calais, France. Sadly, it was not restored, and exposure to the hostile climate of Normandy completely finished off the English veteran. Its armour literally cracked, and its owners sold it for scrap several years ago.

As for the second Cruiser Tank Mk.III, it is not threatened by this fate. It is a representative of a very rare modification, the story of which is not yet fully known. Bovington is in possession of a Cruiser Tank Mk.III*, where the star means that the turret had spaced armour added. It is similar to the spaced armour of the Cruiser Tank Mk.IV, but slightly different. It is not known if all Cruiser Tank Mk.IIIs received this modification. It's possible that work did not progress past experiments, as there were only a couple of dozen tanks left by the summer of 1940.

Original article by Yuri Pasholok.

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