Mark IX tank "The Duck"

The Mark IX was a British tracked supply and infantry carrier designed in September 1917, rather than a fighting tank. Its ungainly shape earned it the nickname "The Pig". It could carry 30 soldiers (officially 50) or 10 tons of cargo. An order for 200 was planned, but only 23 were completed.

Design

There was no time for an entirely new design, so the Mark IX was based on the Mark V with its hull lengthened to 9.73 m. The 150 hp Ricardo engine was moved to the front and the gearbox to the rear, and the suspension girders were left out. This gave an open interior about 4 m long and 2.45 m wide, with large side doors for loading. Heavy cross-girders stiffened the floor. Troops inside had no seats and had to put up with gear control rods along the roof and the drive shaft down the middle. The vehicle weighed 27 tons, had a crew of four and one machine gun, and was badly underpowered, with a top speed of about 6.9 km/h.

The Duck

In 1919 one Mark IX was converted into an amphibian, known as "The Duck". It received a raised cab, buoyancy aids in the form of naval camels attached to the hull, and a modified exhaust. In the water it was driven by an engine at the rear and by paddle-like flaps fitted at intervals along the tracks.