What happened
During a pilot proficiency check, a flight crew was operating an aircraft type during the takeoff phase. The flight began with the pilot-in-command simulating an engine failure by reducing the right engine thrust to flight idle. Shortly after the aircraft became airborne at approximately 18 feet, the pilot ordered the landing gear to be retracted. However, the gear remained extended during the initial climb.
Approximately three seconds after takeoff, a rattling sound was recorded, which was consistent with the deployment of the right thrust reverser. Following this event, the right engine's N2 speed began to decrease. The crew expressed confusion regarding the situation, as the deployment was likely not announced in the cockpit. As the climb continued, the aircraft began a right roll, and the airspeed steadily declined from 149 knots to approximately 132 knots. The aircraft reached a maximum bank angle of about 39 degrees before impacting the ground off the right side of the runway in a nose- and right-wing-low attitude. There were 0 fatalities and 0 injuries reported in the provided text, though the impact was severe.
Findings
Investigation into the accident revealed that there was no evidence of mechanical failure in the flight controls or the engines. While the aircraft remained controllable during previous certification testing with a deployed thrust reverser, the crew was unable to maintain directional control in this instance. The primary cause of the accident was the unexpected deployment of the right thrust reverser.
- The engine's throttle retarder system failed to reduce the right engine thrust to flight idle as designed, which should have occurred within 4 to 8 seconds.
- The specific reason for the inadvertent deployment of the thrust reverser could not be determined.
- No evidence was found to suggest that medical conditions or medications affecting the crew contributed to the accident.