P-39 Expert
Non-Expert
The source is wwiiaircraftperformance.org. Go there and look it up. I am comparing the P-39N (not the M or Q) to the Hellcat, both official government performance tests. Facts. Hellcat and the N had about the same speed at about the same altitude but the N vastly outclimbed the Hellcat at all altitudes.Hellcat's rated altitude for climb was 20000-20500 ft for military power, not 23000 ft.
At 25000 ft, Hellcat climbed at 1280 - 1600 fpm (~12500 lbs, 'overload fighter' condition), P-39M at 1400 fpm (on 7430 lbs, ie. all 120 gals of fuel), P-39N at 1900 fpm (7274 lbs - reduced fuel), P-39Q at 1570 fpm (7871 lbs - ballasted to represent 120 gals of fuel and ammo for all 5 guns, gun pods present), but also just 1365. One does not need to be rocket scientist to see that reduction of weight improves rate of climb, while also reducing range and thence usability. We also have a thing where the Hellcat represents a good manered aircraft (just what was needed for naval fighters), unlike the P-39. Add the double the radius/range and Hellcat is a much more useful fighter.
About the RoF figure of 2285 fpm @ 23000 ft for the P-39N - what is the source?