A number of aircraft have been claimed to be the fastest propeller-driven aircraft. This article presents the current record holders for several sub-classes of propeller-driven aircraft that hold recognized, documented speed records in level flight. Fédération Aéronautique Internationale (FAI) records are the basis for this article.[1] Other contenders and their claims are discussed, but only those made under controlled conditions and measured by outside observers.
Pilots during World War II sometimes claimed to have reached supersonic speeds in propeller-driven fighters during emergency dives, but these speeds are not included as FAI accepted records. They are also extremely unlikely, due to the complex aerodynamic problems of propeller driven aircraft approaching the speed of sound.
Also not formally accepted by the FAI, which was not present due to wartime conditions, are speeds recorded in a dive during high-speed tests with the Supermarine Spitfire, including Squadron Leader J.R. Tobin's 606 mph (975 km/h) in a 45° dive in a Mark XI Spitfire (date unknown) and Squadron Leader Anthony F. Martindale's breaking 620 mph (1,000 km/h) (Mach 0.92) in the same aircraft in April 1944.[2] It should however, be noted that while not FAI certified, the results from Martindale's flight are more than claims. The Royal Aircraft Establishment was a scientific body with the capability to record such events. Martindale's aircraft was fully instrumented with calibrated equipment and had an observation camera recording the flight instruments. Other recording instruments were also fitted. The aircraft lost its propeller and reduction gearbox and was substantially damaged during the test but Martindale managed to successfully land the aircraft, so the data could be recovered and post flight calculations verified the readings.[3]
Flight Lieutenant Edward Powles' 690 mph (1,110 km/h) in a photo-reconnaissance Spitfire PR.XIX PS852 during an emergency dive while carrying out spying flights over China on 5 February 1952 is also discounted. This would otherwise be the highest speed ever recorded for a piston-engined aircraft.[4]