The Eurocopter X3 hybrid helicopter has broken the unofficial helicopter speed record by attaining 255 knots (472 km/hr) in level flight, just days after achieving the fastest speed during a descent of 263 knots (487 km/hr).

Eurocopter achieved the milestone with the X3 flying at an altitude of around 10,000 feet during a 40 minute test flight over southern France near Istres.

"It’s no exaggeration to say that the X3 is clearly in its element at high speeds." said Eurocopter test pilot HervĂ© Jammayrac. "While flying at both 255 knots and 263 knots, the X3 performed exactly as it has throughout its flight envelope, exhibiting outstanding stability and providing a low vibration level without any anti-vibration system."

The X3 is Eurocopter’s technology demonstrator for an advanced, cost-effective vertical takeoff and landing (VTOL) transportation system that offers the speed of a turboprop-powered aircraft and the full-flight capabilities of a helicopter.

It uses a pair of RTM 322 turboshaft engines to power a five-blade main rotor system with two propellers installed on short-span fixed wings.

This article was first published on the Strategic Defence Intelligence website. For more information, please click here.