What happened
On 15 September 2011, a Shadow Series CD, registration G-MYOS, was conducting a private flight when the pilot encountered significant difficulties maintaining the aircraft's attitude. During the flight, the pilot found it necessary to use a higher power setting than usual and significant nose-up trim to maintain straight and level flight.
As the pilot reduced power in preparation for landing, the control stick became heavy and the aircraft began to pitch downwards rapidly. Although the pilot managed to maintain control of the aircraft, the nose pitched up abruptly just before the flare. This resulted in a heavy landing at Craysmarsh Farm, Wiltshire, which caused the tail boom of the aircraft to collapse. There were no injuries to the pilot or the passenger on board.
The investigation
Following the accident, a post-flight inspection of the aircraft revealed the structural failure of the tail boom. The pilot had initially suspected that a runaway trim condition might have been responsible for the control difficulties experienced during the flight.
Investigators examined the electrically operated elevator trim tab. While testing confirmed that the trim system was functioning normally, the repair agency opted to replace the trim system as a precautionary measure.