IN NOVEMBER OF 1942, Koga’s Zero had been extensively repaired. A Hamilton Standard propeller exactly like the Zero’s was fitted because the Zero prop was a copy of a Hamilton Standard. Koga’s Zero 21 had the Sakae 12 engine of 940hp.
Then, flight-comparison tests were flown between the Zero and the current American fighters. The airplanes in this evaluation all had at least 270hp greater than Koga’s. The Zero 52a that I flew had a 1,130hp Sakae 21 engine.
To cancel the temperature or turbulence differences that might happen if tests were done separately, flight tests were flown in formation (up to the point where the planes could keep up with one another). All of the
