Graham Warwick/ATLANTA
The second McDonnell Douglas Helicopter Systems' (MDHS) MD600N prototype was destroyed by fire on 28 May after a crash-landing during flight-testing. The pilot was uninjured.
MDHS says that certification of the eight-seat helicopter, scheduled for September, will be delayed, but believes that first deliveries can still be made before year-end. The aircraft, one of only two tail-rotorless MD600Ns built so far, was undergoing hot-weather flight-testing near Thermal, California.
The pilot was performing control reversals at reduced rotor-RPM, simulating autorotation, moving the cyclic-pitch stick rapidly from fully forward to fully aft in order to determine the extent of blade flapping.
MDHS says that a main-rotor blade struck and partially severed the tailboom, which fell off. Deprived of yaw control, the pilot began an autorotative descent but lost rotor RPM, landing heavily. The skid landing gear collapsed, as designed, absorbing the crash impact. The fuel tank remained intact and no fuel was spilled, but exhaust from the engine ignited the brush in which the aircraft had landed, starting a fire.
MDHS says that completion of the first production MD600 will be accelerated to replace the lost aircraft and that flight-testing on the first prototype will be expanded.
Source: Flight International
