What happened
On 9 October 2015, a ground collision occurred within the maintenance area of Wycombe Air Park, Buckinghamshire. The incident involved a Socata TB21, registration N377C, and a Cessna 152, registration G-WACF.
Following the completion of a flight, the pilot of N377C parked the aircraft near a maintenance hangar. During the engine shutdown process, a ground engineer signaled to the pilot, suggesting the aircraft needed to be moved. Interpreting these gestures as an urgent instruction to perform a 180-degree turn and taxi further into the hangar cul-de-sac, the pilot began the manoeuvre. After completing approximately 130 degrees of the turn, the pilot was alerted by a passenger to an approaching aircraft. The pilot stopped the aircraft, but at that moment, the left wingtip of G-W/WACF passed the right wing of N377C, resulting in the propeller striking the wingtip.
Simultaneously, the pilot of G-WACF was taxiing toward the hangars after landing. The pilot noted that the taxi light and anti-collision beacon were active and observed the ground engineer directing the pilot of N377C to move. The pilot of G-WACF proceeded slowly past the parked aircraft and came to a halt to allow ground crew to move another aircraft. Shortly after stopping, the pilot felt an impact through the control column and heard a sharp increase in noise, realizing the propeller of N377C had struck the wingtip.
The investigation
The investigation examined the actions of both pilots, the ground engineer, and the movements within the maintenance area. The maintenance area, which is not under Air Traffic Control supervision, is a cul-de-sac bounded by four hangars. The investigation established that the engineer had signaled for N377C to move forward to clear the hangar entrance, believing there was sufficient space to taxi approximately 25 to 30 feet.
Findings
- There were no injuries to the crew or passengers involved in the collision.
- The collision resulted in damage to the propeller of N377C and the left wingtip of G-WACF.
- The primary cause of the collision was the misinterpretation of hand and mouth gestures by the pilot of N377C, leading to an unexpected taxiing manoeuvre into the path of the approaching G-WACF.