Eurocopter has begun test flights of the X3 demonstrator for its high-speed, long-range hybrid helicopter (H3) concept.

The X3 demonstrator is equipped with two turboshaft engines that power a five-blade main rotor system and two propellers installed on short-span fixed wings.

The combination creates an advanced transportation system, offering the speed of a turboprop aircraft and the full hover flight capabilities of a helicopter.

The concept is tailored to applications where operational costs, flight duration and mission success depend directly on the maximum cruising speed.

Eurocopter envisages a range of applications for the H3 configuration, including long-distance search and rescue missions, coast guard duties, border patrol missions, passenger transport and inter-city shuttle services.

It also may be well suited to military missions in special forces operations, troop transport, combat SAR and medical evacuation.

Initial testing will continue until December 2010 with reduced power and gradually opening the flight envelope to speeds of approximately 180kt.

Followed by a three-month upgrade, X3 will resume flights in March 2011 with the goal of reaching sustained cruise speeds of over 220kt.