What happened
On 15 January 2015, at approximately 0150 hrs, a British Aerospace ATP, registration G-BTPC, was being prepared for a cargo flight from Coventry Airport to Dublin. The aircraft was carrying roughly 4,600 kg of freight with a crew of two on board. Following the completion of loading and paperwork, the crew initiated engine start procedures. After starting the right engine, the crew signaled for the ground power unit (GPU) to be disconnected. However, the GPU remained positioned directly in front of the aircraft.
Believing the unit was being moved, the commander proceeded to start the left engine and subsequently signaled for the nosewheel chocks to be removed. As soon as the ground crew pulled the chocks, the aircraft rolled forward, striking the GPU. The crew immediately applied the wheel brakes and shut down both engines. There were no injuries to the crew, though the collision caused damage to the nose gear doors, the underside of the forward fuselage, and the top cover of the GPU.
The investigation
The investigation established that the aircraft's parking brake had not been engaged. The commander had assumed the brake was set upon their arrival at the aircraft. While the parking brake was a required item on the pre-start checklist, the crew had failed to complete this checklist correctly. Furthermore, the investigation found that the signal to remove the chocks was issued before the GPU had been cleared from the aircraft's path. The crew was also operating under time pressure, as the flight was delayed and the airport was scheduled to close at 0200 hrs.
Findings
- The parking brake was not set, allowing the aircraft to move once the chocks were removed.
- The pre-start checklist, which included the parking brake setting, was not performed correctly.
- The signal to remove the chocks was given while the GPU was still in the aircraft's path.
- Time pressure related to the upcoming airport closure contributed to the sequence of events.