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The Tank, Infantry, Valiant (A38) was a British tank design of the Second World War that only reached the prototype stage. Intended to meet the specification for a lightweight but heavily armoured tank for use in the war in the Far East, it proved to be an ergonomic failure. The sole example was retained by the School of Tank Technology after the war as a lesson to its students.〔, p.88〕 == Design and development == The Valiant, under General Staff specification A38, began as a candidate for an assault tank, with the thickest armour on the lowest possible weight, for use in the Far East. It was to be similar in intention to the 40-ton A33 Excelsior although far lighter. As the Valiant managed the same 114mm frontal armour with only 27 tons, it managed to achieve its primary goal, but only by making unacceptable compromises elsewhere.〔Fletcher, Universal Tank, p.87〕 At a time when British tank design was already at its nadir, this "terrible price for the weight concession"〔 led to what is probably the worst British tank of the war.〔 The design brief of December 1943 called for three prototypes of a small, heavily armoured tank for the Far East. Speed across open country was less important, as was performance against armour. Design work started with Vickers, but they soon passed it to Birmingham Railway Carriage & Wagon, then finally Ruston & Hornsby, who built the single boilerplate prototype in 1944.〔 Vickers' original intention may have been to use parts of their Valentine infantry tank where possible, but this did not survive the production choices of the other manufacturers, nor was the running gear of the far lighter Valentine compatible with the needs of such heavy armour. The largest point of commonality was the choice of engine, the 210 bhp General Motors 6004 two-stroke diesel, as used in later marks of Valentine. Construction was like that of the Matilda infantry tank - large cast armour pieces bolted together. Suspension was by six equally sized wheels on each side, with independent wishbone suspension units for each, rather than bogies. Concern was expressed about the possible fragility of these units in combat, but Valiant was never taken seriously off-road to test them. The drivetrain was to the rear, from a 210 bhp diesel. This low power limited the tank to a predicted top speed of 12 mph, although this was still acceptable to both the infantry tank and ''assault tank'' concepts. Following from the later Valentine VIII & XI models, the turret was to accept either the QF 6 pdr or the QF 75 mm, with space for a turret crew of three (commander, gunner, loader). This was achieved at the cost of a large heavy turret with near-vertical faces and a massive cast front face with distinctively prominent bolts. The mantlet was internal and a weak point against accurate fire at close range. Unlike the late model Valentines it had a co-axial machine-gun. The Valiant's suspension was tested by the Fighting Vehicle Proving Establishment at Chertsey in May 1945. The first day gave minor problems and was abandoned after only of easy on-road driving. However, the driver was already exhausted by this time, finding that the steering levers needed his full weight to operate and that the seat, footbrake and gearlever all carried risk of physical injury in using them. The Officer in Charge decided to abandon the trials there and then as it was impossible and unsafe to continue, reporting that "in his view the entire project should be closed"〔 There were also issues with weight distribution and the ground clearance of only 9 inches, and by that point of the war there was no longer a need for the tank.〔White, AFV Profile No 6〕 The Valiant project was terminated. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Valiant tank」の詳細全文を読む スポンサード リンク
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