Originally posted by C_R_Caldwell
The AH A6M5b actually outclimbs the new A6M2 with ease.Heck, even the F4F-4 and P-40E can keep up with it, and the FM2 easily outclimbs it. What's the story?
The story is that the A6M2 had a 950hp engine in a 5,313 lbs plane. Powerloading is roughly 5.6lb/hp
The A6M5 had a 1350hp engine in a 5,920 lbs plane. Powerloading is about 4.4 lb/hp, in a much refined plane (IMO, the best of the Zekes) with better aerodynamics, waste gases used for thrust, etc.
So even with the relatively worse wingloading in the M5 version, the MUCH better powerloading of the later aircraft made it a much better climber and accelerator than the early war M2. And in AH ,the A6M5 is indeed a respectable accelerator at sea level.
Remember that many of the fame the early zero won was surrounded by its mith of invencibility. When an A6M2 was captured and tested in comparison tests with american planes, even when it showed to be a good performer, it was no world beater at all. Even a P39D could outclimb it up to 15.000 feet, and the P39D was pure watermelon

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I think the climbrate may be a tad low, thing of 150fpm at SL, but that is my own impression. In any case is nothing as drastic as you seem to claim

BTW this should be discussed in the Aircraft forum
