>You are fairly close to the mark on your comments. The Maybach's were good engines, they do not appear to be the cause of many of the reliability problems that plagued German tanks. Which should be expected, considering that they were developed as specialized tank engines over the course of more than 10 years. However, your criticism of them is also on the mark. They were developed for high horsepower and low torque - not a problem neccessarily in and of itself, especially in the early, lighter German tanks - but coupled with the increased weight of later German tanks and the poor material quality in their later transmissions, it was disastrous. The transmission in the Panther appears to be the cause of 80+ percent of the failures in the late-model Panther, a problem associated with the use of poor quality steel in the gearing (there was barely enough hi-quality steel available for the better-made Tiger transmissions) and the overly-complicated, multiple gear design.

>But as to the US tank engines, that was a product of parsimony and short-sightedness, as well as some good luck and clever engineering. The original US "tank" engine was nothing of the sort. It was actually a de-rated radial aircraft engine. Designing tanks around them was a matter of economy, decided on in the 30's. The engines were light weight, with excellent power output and torque, but were also bulky and were fuel hogs.

I know nothing about engines whatsoever, and I am trying to find out about tank engine possibilities for an alternate history excercise. I know that the Germans had some trouble finding suitably powerful engines for Tigers and Panthers, but had various aerial and ship engines around that were more powerful. Would either their aircrafts' radial engines,or the engines used in warships have been adaptable for use in a heavy tank? If so, what drawbacks would this have entailed, and when would such engines have been available? Specifically,I am looking at what possibilites would be available in the period 1932-1939, though later developments would still be of some relevance to me. I am looking for an engine to power 50-75 ton vehicle along the lines of the unfinished Panther.2 or E series.

Also, can anyone tell me how the slope of a vehicle's body would affect the usable volume, and therefore weight? I know nothing about engineering,and my 3D-geometry is very shaky. The only source I found so far to discuss this was a vehicle design book for a role-playing game. (GURPS Vehicles, 2nd Ed.) This book contained a formula for slope implying that sloping the sides of an AFV was counterproductive in terms of lost volume for equipment and crew, and the additional structure that would need to be added to compensate. Of course, this does not seem to make sense, logically.