The two stage Allison in the P-40Q still didn't have the altitude performance of a Merlin P-51 or a P-47 and the engine itself was known to have not always performed as advertised. The Air Force was not happy about using it in F-82s after the Merlin production license expired.
I stand corrected, to a degree. From what I can see, the only models that climbed at that rate were the L and N-1 models which benefited from drastic weight reductions including removal of 2 guns and among other things a significant reduction in fuel capacity. That's especially the case for the...
You're confusing two stage supercharging with two speed supercharging, or the author of your reference is. There were no B-17s captured in the CBI. If there was one used for practice, it would have had to be on of the three captured in the Philippines or Java, which given the time frame is...
It's a thinly vailed ad for the export model of the P-36. USAAC P-36s did not have armor, 4 wing guns, the ability to carry under wing cannons , or bomb racks.
All those aircraft had two speed superchargers which could be shifted to high and low blower speeds. What would be the purpose of a single speed supercharger that could be disengaged?