The US Army Air Corps accepts its first helicopter (Sikorsky XR-4)

Saturday, May 30, 1942



Colonel Frank Gregory headed the evaluation team. The XR-4 was the world's first mass produced helicopter and the first successful production rotorcraft with a single rotor configuration.

The aircraft had been delivered (by Ralph Alex, project officer on the helicopter) to Wright Field on May 17 1942 after a cross-country flight from Stratford, Connecticut.

Source: Smithsonian National Air and Space Museum | Collections | Vought-Sikorsky XR-4C | Long Description, Accessed April 16, 2016


Aircraft related to this milestone
Sikorsky XR-4

Related biographies
Ralph Alex
H. Frank Gregory