Originally posted by panther3485
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Originally posted by panther3485
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As an example, the US staged a race between the T25E1, T26E1, M4A3E8, and M4A3 VVSS in Aberdeen's Churchville cross-country area. The T25E1 and T26E1 both ran on torsion bars. All tanks had the same engine, however: the GAF of the T25/26 was essentially the GAA of the M4A3 redesigned to present a lower height, but power output was the same. The T25E1 and T26E1 were the heaviest vehicles in the competition, and as was shown in Korea, the relatively low power-to-weight ratio of the M26 compared to the M4A3(76)W HVSS yielded poorer performance in climbing the steep mountains of that country. Steering was controlled differentials for all the vehicles.
So the stage was set. All tanks had the same engine power output, and steering, but the heavier tanks were running on torsion bars instead of the volute spring suspensions of the lighter and intuitively more nimble Shermans. The results, however, had the torsion bar tanks in first place by a healthy margin: M4A3 finished in 30:40, the M4A3E8 in 28:35, the heavy T26E1 in 26 minutes, and the T25E1 in 23 minutes.
Looking at a comparison of British tanks, Cromwell had bump suspension travel of 226 mm and rebound of 190 mm, yielding 416 mm total. Churchill had bump travel of 3" (76 mm) and rebound of 2" (51 mm) on its bottom suspension bogies. Churchill's springs would necessarily be stiffer than those of Cromwell or else Churchill would be bottoming out on its bump stops constantly. With these stiffer springs, Churchill would be imparting higher bounce forces to its crew over a given terrain, and these forces would limit the vehicle's speed through rough terrain. Churchill could cross ditches or soft ground better than Cromwell due to its shape and lower MMP, but Cromwell should be able to cross hard, broken ground faster.
Originally posted by Nick the Noodle
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Originally posted by Nick the Noodle
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