Did you know…
Who flew the Mustang prototype's first flight?
Short answer
The first flight of the NA-73X prototype was made by Vance Breese, an independent test pilot, on 26 October 1940 at Mines Field (Los Angeles), today the city's international airport. The flight lasted five minutes and the aircraft carried civil registration NX19998. Breese had already flown other first flights for various manufacturers.

Five minutes over Mines Field
On 26 October 1940 the North American Aviation prototype designated NA-73X made its first flight at Mines Field in Los Angeles, California, the airfield that is today the city's international airport. The aircraft carried no military markings, only a civil registration, NX19998, and the flight was brief: five minutes in the air. From that airframe would emerge the fighter that would become known as the P-51 Mustang.
Vance Breese, freelance test pilot
At the controls was not a pilot on the manufacturer's payroll: the flight was carried out by Vance Breese, who worked as an independent test pilot. He was a well-known name in that line of work, with several first flights to his credit and flight-test campaigns carried out for different aircraft manufacturers, so entrusting him with the NA-73X's debut fit his track record. Breese was born on 20 April 1904 and died on 26 June 1973; the Society of Experimental Test Pilots went on to recognize him as an Honorary Fellow.
A Dictaphone and a movie camera on board
Breese also left his mark on how test flights were documented. He pioneered procedures that were not common at the time: he recorded his notes aloud with a Dictaphone instead of relying only on paper, and he mounted a movie camera to film the instruments while flying. With that dual record, the panel readings and the pilot's comments were preserved just as they had occurred in the air, rather than depending on what the pilot might recall after landing.
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