The Accident
On 10 March 2015 at 1402 UTC, a Kolb Twinstar MkIII aircraft, registered G-MZGJ, departed from Runway 25 at Otherton Airfield, Penkridge, Staffordshire, on a private flight with one pilot and one passenger. Shortly after takeoff, while performing a shallow left turn at approximately 450 ft, the pilot encountered a restriction in the pitch control. The aircraft began to descend and the pilot was unable to maintain altitude.
Sequence of Events
The pilot initiated a forced landing. During the latter stages of the approach, the left wheel struck a wooden post, causing the aircraft to yaw left. The left landing gear dug into the ground, and the aircraft slewed left before skidding to a stop after approximately 15 metres. Neither the pilot nor the passenger sustained any injuries.
Examination Findings
The pilot reported that a full control check had been performed before takeoff with no anomalies. After the forced landing, the control restriction was no longer apparent. The Light Aircraft Association (LAA) examined the aircraft and concluded that the control restriction was probably caused by excess slack in the elevator control cables, which allowed them to contact the tail boom. Additionally, bulky clothing worn by the pilot may have exacerbated the effect by pushing a turnbuckle against the side of the boom, temporarily restricting the controls.
Aftermath
The LAA indicated that they would write to UK-registered Twinstar owners, reminding them of the importance of maintaining correct cable tensions and the risk of clothing interfering with controls. They also planned to increase general awareness by discussing the occurrence in their publication, 'Light Aviation'.