DA-42 ulykke i USA i august - Jammed Flight Controls - AVweb

 

August 9, 2021, Hiddenite, N.C.

Diamond DA42 Twin Star

The airplane was substantially damaged at about 1335 Eastern time when its crew reportedly experienced a jammed pitch control. The flight instructor (CFI) and a private pilot were not injured. Visual conditions prevailed.

After completing several maneuvers and simulating emergency procedures, the two initiated a simulated left engine fire and emergency descent. The left engine was shut down, with its throttle, propeller and mixture controls fully closed. During the descent, the attitude and heading reference system (AHRS) failed and the CFI directed the private pilot to recover “gradually and easily” at 3500 feet msl and maintain 90 knots as the AHRS displayed a message that it was aligning/calibrating.

The CFI had noticed the airspeed had increased through 100 knots and altitude had decreased to about 3000 feet when the private pilot stated, “I can’t pitch up.” About this time, the right engine—the only one operating—began to sputter. The CFI took control, moved the mixture, propeller and throttle controls for both engines fully forward, and ensured the landing gear and flaps were up. However, he also was unable to increase the pitch and stop the descent, later reporting “it felt as if we were unable to fully pull the control stick back, as if it were restricted preventing full movement.” Both engines regained power, but he felt they “were not producing normal operation power.” After selecting a landing area, the CFI kept his hands on the control stick as the private pilot lowered the landing gear and added full flaps for landing. Subsequently, the airplane touched down nose-low in a soybean field, impacted a ditch and skidded to a stop.

Initial examination established flight control continuity. The manual elevator trim wheel indicated a slight nose-down setting. The autopilot circuit breaker was found pulled and collared. Both wing tanks contained fuel and no oil spray was observed on the engine cowling or fuselage.