12/31/2008. Remarks by Johan Visschedijk: "Donovan 'Don' R. Berlin (who designed the P-36 and P-40) moved from Curtiss to Fisher in April 1942, and started the design of an aircraft to meet an USAAF requirement (issued in February), for a fast climbing high-altitude fighter. The proposal was submitted in September, on October 10 a contract was placed for two XP-75 Eagle prototypes, s/n 43-46950 and 43-46951. To speedup construction, P-40 outer wing panels, an A-24 tail unit and an F4U main landing gear were used.

Only nine months later, July 6, 1943, an additional six aircraft were ordered to be developed into long-range escort fighters, designated XP-75A Eagle, s/n 44-32161 to 44-32166, while Fisher also received orders for 2,500 production P-75As, s/n 44-44549 to 44-47048. The first XP-75 made its first flight on November 17, 1943, the second XP-75 and the six XP-75As all were flying by spring 1944.

The first P-75A production aircraft flew on September 15, 1944, however, production was halted three weeks later, while the contract was cancelled on November 8, 1944, after five aircraft, s/n 44-44549 to 44-44553, had flown, the sixth finished, s/n 44-44553, was never flown. P-75A, s/n 44-44553, is preserved at the National Museum of the USAF."