Eurocopter's X3 achieved an unofficial helicopter speed milestone on June 7 by attaining 255 knots true airspeed (KTAS) (around 293 mph or 472 km/hour) while in level flight. The company also reports that several days before that flight, the X3 reached a speed of 263 KTAS (about 303 mph or 487 km/hour) during a descent.
X3 in-flight with an Albatros AL39. Photo courtesy of Eurocopter
The 255-knot speed milestone occurred during a 40-minute test flight over southern France at an altitude of 10,000 feet. For the flight, Eurocopter used a pair of Rolls-Royce Turbomeca RTM322 turboshafts to power its X3 technology demonstrator.
By achieving the 255-knot mark, Eurocopter goes over Sikorsky's unofficial helicopter speed record
set on Sept. 15, 2010 with its X2 technology demonstrator, which reached speeds of 250 KTAS in level flight and 260 KTAS in a shallow dive. Sikorsky retired the X2 prototype, precursor to the S-97 Raider military variant, in July 2011.
Related: Airframe News