Mark VIII tank

The Mark VIII tank also known as the Liberty or The International was a British-American tank design of the First World War intended to overcome the limitations of the earlier British designs and be a collaborative effort to equip France, the UK and the US with a single heavy tank design.

Production at a site in France was expected to take advantage of US industrial capacity to produce the automotive elements, with the UK producing the armoured hulls and armament. The planned production levels would have equipped the Allied armies with a very large tank force that would have broken through the German defensive positions in the planned offensive for 1919. In practice, manufacture was slow and only a few vehicles were produced before the end of the war in November 1918.

After the war, 100 vehicles assembled in the US were used by the US Army until more advanced designs replaced them in 1932. A few tanks which had not been scrapped by the start of World War II were offered to Canada for training purposes.

Early development

As the First World War progressed, the industrial production capacity of the Entente was taxed to the limit. Of the Allies, only Great Britain and France had been major industrial nations in 1914 and the latter had lost 70% of its heavy industry when the Germans overran that part of Lorraine that they had not already occupied in 1871. The output in Britain was limited by labour shortages due to the manpower demand of the armed forces and a rocketing national debt.

When the United States of America declared war on Germany on 6 April 1917, many in Britain hoped this event would solve all these problems. The two men directly responsible for British tank production, Eustace Tennyson d'Eyncourt and Lieutenant-Colonel Albert Gerald Stern, initially considered sending a delegation to the United States immediately, to convince the new ally to start production of a British tank design. After some reflection they decided it was best to leave the initiative to the Americans. Stern did contact the American Military Attaché in London immediately after war was declared. In June 1917 the first American approaches were made, but not by the US Army as they had expected. The US Navy wanted the most modern tanks for its US Marine Corps. At that moment the current British tank project was the Mark VI. It was designed with existing British industrial capacity in mind, posing limits that might be overcome by larger American production facilities. Stern therefore pretended that an even more advanced project had already been in existence which he called the Mark VIII (there was also a much more conventional Mark VII project). He invited the Americans to participate and contribute as much as they would like to its design. The Navy was on the brink of sending a team of engineers to Britain when the American Department of War was informed of developments by the US Military Attaché in London. It ordered the project to be shifted to the Army and selected Major H. W. Alden – in peacetime he had been an industrial expert – to go to the UK to work with the Mechanical Warfare Department design team at Dollis Hill on the first drawings of the new tank. He arrived in London on the 3 October, to discover that a lot of design work had already been done by Lieutenant G J Rackham, who had been sent to the Front to see for himself how the current designs performed in the dismal conditions then encountered at the battlefield in Flanders. The Army tried to convince the Department of War to divert all available tanks to the Army, leading to a conflict with the Navy (the first of many to come over this issue). This posed serious problems for the British government. It now seemed that American involvement in the war would mean a lesser number of tanks available for the British forces. Also on 4 February 1917 binding agreements had been made with the French about tank production. These had to be renegotiated.

Winston Churchill, the new Minister of Munitions, had just been forced to fire Stern as director of the Mechanical Supply Department (Controller of the Mechanical Warfare Department) because of his mistakes in handling the Mark IV project, leading to enormous production delays. In pushing production through in the early days he had upset civil and military authorities. fitted for battle as the armour plate was thin with a thickness of 16 mm on the front and sides—a slight improvement over the Mark V but very thin by later standards. The roof and bottom of the hull were protected by only 6 mm thick armour plate, leaving the tank very vulnerable to mortar shells and landmines.

Production

The French government hoped to receive 700 Mark VIIIs for free, as the French superheavy tank, the Char 2C, could not be produced in sufficient numbers, if at all. However, suffering from a lack of manpower and raw materials the French were not forthcoming in providing any facilities for the production of the International Tank. Soon the Americans decided to build a brand new assembly factory at Neuvy-Pailloux 200 miles south of Paris, contracting a British company. Far from producing its first tank in April, the factory was not even finished by June. In August they contracted another British firm. It finished the factory in November, by which point the war had already ended; not a single tank would be built there.

There were also serious delays in the production of the components. The Liberty aero engine with its expensive drawn-steel cylinders was redesigned with cheaper cast iron cylinders. These redesigned engines were only produced in October. In spite of these delays, there were plans to produce a further 1,500 tanks in the United States on top of the shared production in France. This was not possible due to lack of armour and guns so the extra production was to be in France as well. Only then was the armament shipped from Britain, and two guns and ten Hotchkiss machine guns were fitted.

Testing was finished after the war and it was decided to build 100 vehicles in the USA; these were constructed in 1919 and 1920 by the Rock Island Arsenal for $35,000 each. The US bought 100 complete sets of parts for the hull from the British, the whole amount that had been completed.

Meanwhile, the British government had decided to start their own production in Britain. One thousand, four hundred and fifty vehicles were ordered from the North British Locomotive Company, William Beardmore and Company and Metropolitan, to use a V12 Ricardo engine instead of the Liberty. Only the first managed to produce anything by the end of the war with seven vehicles built. was tested on 11 November, the day of the Armistice.

From parts already produced a further 24 vehicles were completed after the war. Five were sent to the training centre at Bovington in Dorset, and the others went straight to the scrap dealer.

Mark VIII*

During 1918, the then prevalent preoccupation with trench crossing capabilities led to preparations being made for the production of an even longer tank: the Mark VIII* (Star). The hull was to be lengthened a full three meters: at the front and at the back. This way it should be able to cross a trench wide. To ensure that the tank could turn at all, despite its critically high length-width ratio, the bottom profile of the tracks would be more strongly curved, so that a smaller part of the track would touch the ground. Ground pressure would have increased however, as total weight reached 42.5 tons (43.2 tonnes). If the tank had sunk into soft ground somewhat, it's questionable whether it would have been able to make a turn. No prototype was built.

Operational history

The American Liberty tanks equipped a single unit: the 67th Infantry Regiment (Tank), based in Aberdeen, Maryland. The curious designation of the unit had its origin in the fact that since 1920, by law, all tanks had to be part of the Infantry branch. The two machine gun positions at the sides of the superstructure were eliminated, so the crew could be reduced to ten. Water-cooled M1917 Browning machine guns were used. Despite many modifications, the vehicles suffered from overheating and poor reliability, causing a prejudice in the Army against the use of heavy tanks. From 1932 onward they were phased out; all were in storage by 1934. In 1940, Canada had a lack of training tanks and were offered the remaining tanks at scrap value, but the Canadians instead opted to purchase M1917 light tanks.

Notes

Bibliography

Preliminary Handbook of the Mark VIII Tank