[Joeaksa]

Normy,

One thing you are forgetting. Throw much of the metalurgy issue out of the argument. Its correct but its not the main thing here.

First our oils back then were not 1/10th as good as the are now and engines were worn out after as little as 25-50 hours. The ME-262 engines were lucky to last 25 hours and this was due to both metalurgy AND oils that would not take the jet engine temps.

Second of all on why the B-17 was climbing slow was that back during the war and until the 1970's we had 115/145 "Purple" avfuel. It was made for wartime use and thats a large part of what won the war for us was that we had the fuel that allowed our airplanes to produce more power without detonation, which allowed us to fly higher, futher and carry a bigger load.

Refineries stopped making "purple" gas years ago but I still remember using it on my SCCA Austin Healey race car. Crank the advance up there and it could care less but that was with excellent gas. These days the old WW2 engines have to retard their timing to operate with 100ll fuels and they are way down on power, so cannot make the boost that they were normally limited to, which keeps them from climbing so fast.

Simple answer, long to explain. Read the ops manual on a P-51 and see what the boost limits are. Then talk to a Mustang pilot today and see what he can use without grenading the engine with todays fuels. Bet that its half the limits...

Joe