Quote Originally Posted by tankersteve View Post
First, as hot as the exhaust is, it really isn't THAT hot. I never saw a Goretex melted by infantry guys inches away, drying out gear. The idea that you can't work around it is just silly. However, the exhaust deflector, commonly constructed by the unit welder, alleviates almost all of this issue for working in/around tanks. Further, there is a deep-water fording kit (costs money and usually just USMC tanks) that also achieves this.

There are relatively few heat-seeking ATGW. Most are laser-guided or SACLOS systems. It does hinder hiding from aircraft and thermal viewers, but the quick-starting and accelleration were considered acceptable trade-offs back when the tech was new.

Finally, infantry don't ride on the back deck. They ride on the turret. I have slept on the back deck and it does get hot, but not so much that they couldn't do it. But the old FM 7-8 has them on top of the turret.
Appreciate the argument re alternatives. However, infantry should be able to shelter behind a tank and use its intercom/phone without being tanned or toasted. Also infantry or combat stores that may have to ride on a tank are likely to better protected on the engine deck behind the turret rather than on top of it exposed to overhanging vegetation and incoming fire.

The capabilities of heat seekers have been continuously improved. And even when diverted and diffused the large volume exhaust from a 1,500hp gas turbine provides a more detectable and trackable target than the exhaust of a 1,500hp diesel. So why not a diesel Abrams and the related benefit of a well protected and presumably quieter APU ?

In terms of fuel and probably also maintenance, gas turbines are relatively expensive to operate. They also need routine refurbishment and when practicable upgrades to reduce maintenance and operating costs. Hence the AGT-1500 Tiger program which reportedly passed $1.5billion in 2010. It was also intended that the AGT-1500 be replaced by a more economic and compact LV100-5 gas turbine. But bracketed with Crusader, that engine project evaporated with cursory explanation and little comment.

For reasons presumably well understood and agreed within GE at least, company funds have recently been spent on building a ‘prototype’ diesel Abrams chassis. So has something changed ? Or is that prototype just a speculative venture offered in the hope that some party somewhere just might become interested in a diesel Abrams MBT ?

Possibly and/or a diesel Abrams ARV and/or AEV ?