The Medium Mark III
was a medium tank developed in the United Kingdom
during the inter-war period
. The tank was unsuccessful with only 3 built. The design did not directly derive from earlier Medium Mark II
A6 "Sixteen tonners"
In 1926, the British War Office wanted to replace their existing Mark II tank
with a new design. In May the Royal Tank Corps
Centre was asked for its opinion, which it submitted in July. One of the requirements was a weight limit of 15.5 tons, which led to the nickname "16-tonners". Other specifications included that it could transported by rail; a sufficient supply of lubrication oil to match the range of the tank (dictated by the fuel carried); a wireless set; a gun capable of defeating enemy armour at a range of at least a thousand yards; fuel tanks external to the main compartments and bottom armour sufficient to withstand heavy machine-gun fire when exposed while climbing a crest. Furthermore the machine should be as silent as possible, as with previous types the engine noise tended to incapacitate the crew.
The War Office
added some extra requirements: a separate engine compartment; superior steering capacity and 13 millimetres frontal armour with 9 millimetres thickness for the other plates.
In September Vickers, given the order to build a prototype, proposed a first design based on the Vickers A1E1 Independent
, with the fighting compartment in front and the engine compartment at the back.... Read More