Warbird Information Exchange

In the case of the Zero, Jiro Horikoshi later provided an articulate and detailed argument to reject that it was a copy of any foreign aircraft. True, the engine was derived from the Pratt & Whitney Twin Wasp, the propeller was a Hamilton Standard design, the flight instruments were copies or license builds of foreign designs, and the guns were all basically licensed foreign designs as well, but such technology trading was common in the design of aircraft of other nations.