First flight of largest diameter main rotor ever flown (Hughes XH-17)
Tuesday, September 16, 1952
This was the largest diameter main rotor ever flown at 130 ft . First flight was by pilot Gale Moore. The first flight lasted approximately 1 minute and the aircraft attained an altitude about 1 foot. The flight was terminated due to high pedal forces. For an extensive description of the flight development program and background to the design see the source below.
To see a video of the helicopter in flight, click this link.
Source: "The Hughes XH-17 Flying Crane", Ray Prouty, VERTIFLITE Fall 2005, Page 56