Eurocopter’s compound helicopter demonstrator, the X3 (“X cube”), met its first speed target on November 29 when it achieved 180 ktas in level flight at “reduced engine power.” The modified Dauphin has also expanded its flight envelope in altitude and bank angles. The X3 features a conventional main rotor and two propellers on stub wings.
Flying from Istres, southern France, the aircraft has reached 12,500 feet and has performed maneuvers with left and right turns and bank angles of “up to 60 degrees.” Eurocopter said the flight envelope has been opened “with and without autopilot to validate stability and handling characteristics.”
According to test pilot Hervé Jammayrac, handling and flight qualities are “exactly in line with ground-based simulator evaluations.” The aircraft will soon have its main gearbox upgraded for the second phase of flight tests, which aim to demonstrate a cruise speed of 220 knots. Design engineers have calculated 220 knots to be an economical sweet spot where speed is profitable.
The X3 was unveiled on Sept. 27, 2010.