Flying the aircraft at varying altitudes and speeds beyond maximum operation limits, the high-speed flutter test demonstrated sufficient margin on the normal operating envelope of the MRJ. Testing for flutter – a phenomenon that occurs when aerodynamic forces cause rapid self-excited destructive vibration – required a heavily instrumented aircraft operated by well-trained crew that was monitored by engineering specialists on the ground.
As a prerequisite to the type certification lightning test later this year, we completed an internal simulated lightning strike assessment on Flight Test Aircraft 5 (FTA-5) in December 2016 in Nagoya, Japan. To simulate lightning strikes, we applied a low electrical current to the aircraft, which produces a magnetic field around certain areas of the aircraft, such as the ports, engines and the edges of the empennage on the tail.
Required for all new clean-sheet design aircraft, the Full-Scale Static Strength Test ensures the aircraft’s ability to meet structural strength safety standards and comprises testing of the wings, vertical stabilizer and fuselage. The test rig, a system of hydraulic actuators positioned to distribute force across the airframe simulating operating loads, was designed and manufactured by Mitsubishi Heavy Industries at a facility near the Nagoya Airfield in the Aichi Prefecture, Japan.