Mark II (Female) Heavy Tank from the left |
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The Mark II Tank was originally built as a training vehicle, but a number were rushed into action at Arras in 1917, despite lacking proper armour.
Although the combat debut of the Mark I Tank hadn’t quite lived up to expectations, it was clear that the new weapon had a great deal of potential. As a result General Haig had demanded 1,000 new tanks. The Mark I design had a number of clear flaws, so the aim was to build these as the improved Mark IV. While this tank was under development training tanks would be needed, so it was agreed to build fifty Mark II Tanks and fifty Mark III Tanks. The Mark II would be similar to the Mark I, while the Mark III would be more similar to the Mark IV. In practise the two models of training tank would be rather similar to each other.
The basic layout of the Mark II was the same as on Mother and the Mark I. It had the familiar rhomboid tracks going all the way around the vehicle, with a box like fuselage between the tracks. It was powered by the same 105hp engine with the same complex steering mechanism as the Mark I. The forward turret was made narrower to allow for the use of wider track shoes, although it isn’t clear if they were every used. Some sources say that wider track shoes were installed at every sixth link and they do appear on some photographs of the Mark II. The Mark II was given a raised manhole hatch on top of the fuselage, which allowed a crewman to look out of the tank with some protection.
Production of the 50 Mark II Tanks was split between Fosters at Lincoln and Metropolitan. Fosters built the 25 Males (serial numbers 776 to 800), and Metropolitan the 25 Females (serial numbers 576 to 600). The first Mark II to be completed was a Male built by Fosters in January 1917.
Although the Mark II was intended as a training machine, in the end all but five of them were used in combat, while the remaining five were used to test new power, gear and steering systems.
Major Walter Wilson, one of the designers of Mother, had never been happy with the complicated steering mechanism, but had accepted it because it used existing machinery. In the autumn of 1916 he suggested using epicyclic or planetary gears, which would eliminate the need for gearsmen and allow a single man to drive and control the tank. However Albert Stern, who was in overall command of tank production, wasn’t convinced and decided to carry out a competitive trial. Five Mark IIs were taken from the production line to be used as the test vehicles. Stern himself had been impressed by the petrol-electric system being developed in France for the St. Chamond heavy tank, and decided to have Mother rebuilt with a Daimler petrol electric system.
The trials took place at the Oldbury Testing Ground on 3 March 1917.
The Daimler petrol electric system in Mother used a 125hp engine which powered a dynamo that powered two electric motors. The power levels were controlled by directly adjusting the brushes in the dynamo and engines, giving it a very jerky motion.
The first Mark II was given to Wilson, who installed his planetary final drive system. This used a 105hp engine that sent power to a conventional gear box with four forward speeds and one reverse. Power from this went to the epicyclic gear. To steer the tank the drive pulled a brake lever that caused one of the gears to idle, leaving the other track powered. On the day of the trials the engine was failing, so the entire drive didn’t perform well. However with a working engine it carried out a 300 mile test run without problems.
The second Mark II was given a Williams-Janney hydraulic drive. This was powered by a 105hp engine, which drove two hydraulic pumps. These in turn powered hydraulic motors in the track frames that were connected to the drive sprockets. In theory this system allowed for very fine control of speed, while steering was controlled by altering the speed of the pumps. Unfortunately the hydraulic pumps produced so much heat that a series of radiators had to be installed between the rear horns, which would have been impractical in combat. This was an adaptation of the company’s gear used to rotate naval gun turrets, which tended to have rather more space available for the gear.
The third Mark II was given a British Westinghouse petrol electric drive. This had a 115hp Daimler engine, which was moved further back in the tank than normal. This powered two dynamos that drove a pair of electric motors at the rear of the tank. This was the same basic idea as the system used on Mother, but power was controlled by tramcar controllers which provided it with much smoother controls and power.
The fourth Mark II was given the Wilkins Multiple Clutch system, a rather complex system that had power from the engine go to a bevel gearbox that then powered one gear box on each side. Each of these gearboxes had three forward and one reverse speed, controlled by a series of clutches that meant that only one gear could be selected on each side at a time. In theory it was possible to change gear while moving, but it was considered to be overly complex and requiring a great deal of driver skill. However on the day of the trials this tank failed to start, so didn’t take part.
The fifth Mark II had been sent to St. Chamond to get their petrol electric drive, but wasn’t completed in time to take part in the trials.
A newly built Mark IV (or modified Mark I), the Tritton Chaser (which became the Whippet), and the prototype Gun Carrier also took part in the trials. Wilson considered that the Mark IV performed best, presumably because its crew had experience with its drive system from earlier models.
After the trials Wilson’s epicyclic system was chosen for the Mark V, while an option on the William-Janney system was take for a later model. It would eventually be used in the Mark VII Tank, of which only a handful would be built, and to control the jib in the Mark V** (RE Tank).
Combat
The Mark II had never been expected to have to fight, but by March 1917 it was clear that none of the new Mark IV Tanks would be ready for combat in time to take part in the upcoming spring offensive. The Heavy Branch in France reported that only fifteen of the original Mark I Tanks were ready for combat, leaving them desperately short of tanks.
There were already nineteen Mark II tanks in France serving with training units. Now the remaining twenty six came over from Bovington, giving a total of 45 Mark IIs available for combat. In an attempt to provide some armour protection, some of the Mark II Female tanks were given the armoured sponsons from damaged Mark I Females. These can easily be identified as they still carried the elaborate camouflage paint scheme used on the Mark I but abandoned on all later versions after it became clear that the tanks would soon be coated in mud.
The tanks had little impact on the fighting at Arras. All eight of the tanks that had been allocated to support the Canadian attack on Vimy Ridge got bogged down and missed the battle. Forty tanks were allocated to the main attack, due east of Arras itself. Once again many of these broke down or got bogged down in their long approach march, leaving a handful of tanks to take part in the battle. Some of these tanks performed well. The male tank Lusitania from C Battalion, commanded by 2nd Lt Charles Weber, helped capture Feuchy Redoubt and Feuchy Chapel, before it ran out of fuel while supporting another attack. Weber was awrded the Military Cross. To the south twelve tanks were allocated to support the 4th Australian Division as it attacked close to the main Hindenburg Line. An initial plan to string the tanks out along the line was altered in favour of concentrating them for a concentrated attack on part of the German lines. However this was too ambitious – the tanks were repeatedly delayed reaching the front, and the attack ended up being delayed. When it did go ahead, on 11 April, some of the tanks performed well, but the overall impression was poor. As a result the Australians discounted tanks until the summer of 1918. On the German side two tanks were captured, allowing them to identify their vulnerabilities. However this was just about the last gasp for the Mark I and Mark II, and the Mark IV had some of those flaws fixed.
Names
Stats
Production: 50
Hull Length: 32.5ft
Hull Width: 13.75ft (male); 14.33ft (female)
Height: 8ft
Crew: 8
Weight: 28 tons (male), 27 tons (female)
Engine: 105hp Daimler-Foster gasoline engine
Max Speed: 3.7mph
Max Range:
Armament (Male): Two 6-pounder guns and four machine guns
Armament (Female): Five machine guns
Armour: 6-12mm