Nation of Origin: Iosia
Role: Experimental/ Naval Fighter - Never finished
First Flight: 18th May 1955
Introduction: Never fully introduced
Status: Retired January 9th 1957 - 2 on display
Number Built: 5

An aircraft doomed from the start, the XF-90 (unofficially named Banshee) was an experimental turboprop aircraft powered by a turbine engine that was mated to a supersonic propeller, the Banshee had the potential of setting the unofficial air speed record for propeller-driven aircraft, but was unable to overcome multiple deficiencies, resulting in the program's cancellation and ultimate scrapping.

The XF-90 is quite possibly the loudest aircraft ever to be developed as reports have been made that prototypes of the Banshee could be heard as far as 25 miles (40 km) away. Unlike standard propellers that turn at subsonic speeds, the outer 24–30 inches (61–76 cm) of the blades on the XF-90's propeller traveled faster than the speed of sound even at idle thrust, producing a continuous visible sonic boom that radiated laterally from the propellers for hundreds of yards. The shock wave was actually powerful enough to knock a man down; Multiple reports had been made of severe nausea and migraines from ground crew near the aircraft, even whilst idling. One report of bowel ejection has been noted, but unconfirmed.

Inspired heavily by the XF-84H Thunderscreech