Eurocopter is reporting a new breakthrough in the test flight program for its X3 high-speed, long-range Hybrid Helicopter demonstrator. The aircraft is equipped with two turboshaft engines that power a five-blade main rotor system and two propellers installed on short-span fixed wings, combining the vertical takeoff and landing (VTOL) capabilities and full hover flight capabilities of a helicopter with the fast cruise speeds of a turboprop-powered aircraft. On November 29, the X3 reached the program’s Step 1 speed objective by attaining a true airspeed of 180 knots (333 km/h or 207 mph) in level flight at a reduced engine power level.
The X3 demonstrator’s maiden flight took place on September 6, 2010 in Southern France at the Istres Center of “DGA Flight Testing”, and since then the basic hybrid demonstrator aircraft’s stability and handling has been tested both with and without autopilot. It has reached an altitude of 12,500 feet (3,810 m) and performed maneuvers with left and right turns at bank angles of up to 60 degrees. With initial testing operating on reduced power, the flight envelope was progressively opened to achieve the 180 knot milestone.
The X3 has performed extremely well, demonstrating handling and flight qualities that are exactly in line with our ground-based simulator evaluations,” said Eurocopter test pilot Hervé Jammayrac. “This helicopter is really built for speed, and our test team looks forward to taking the X3 to the next steps of its flight regime.”
After a three-month upgrade the X3 is set to enter a second set of flight tests in March 2011, with the goal of reaching sustained cruise speeds in excess of 220 knots (407 km/h or 253 mph) – which, it should be noted, still falls short of the 250 knots (463 km/h or 287.69 mph) record achieved by Sikorsky Aircraft’s coaxial X2 Technology demonstrator in September this year.
The X3 is built around a Eurocopter Dauphin helicopter frame and is designed to suit a wide range of applications, including long-distance search and rescue (SAR) missions, coast guard duties, border patrol missions, passenger transportation and inter-city shuttle services. Eurocopter says it could also be well-tailored for military missions in Special Force’s operations, troop transportation, combat SAR and medical evacuation.