Quote Originally Posted by Seamus Fermanagh View Post
The B-29s "achilles heel" was a tendency for engine overheating. This would cause it to lose an engine (feathered and shut down to prevent fire) every so often. At altitude the sucker could fly on 2 engines. However, if loaded near its full gross (bombs fuel etc.) and it lost an engine on takeoff, there was a pretty good chance it would crash/crash land.

However, with all 4 engines healthy, it could take its normal bombload (9,000kg) up to 10,000m+ (unloaded it could be nursed to 12,000 m), cruise at 360kph and crank it to 500+ kph at need. Total operational weight is always a product of fuel needed, bombload desired, and distance to/speed to target. A 29 could haul 20,000kg of bombs on shorter trips with diminished speed and agility.

The problem with the early a-weapons was their bulk rather than their total weight. The 29 was the only plane in the inventory with a bomb-bay big enough to deploy the "Fat Man."
Weren't the engine problems largely taken care of by the end of WWII though?