What happened
On 20 January 2006, an ATR 42-300, registration G-TAWE, was preparing for a night passenger flight from Glasgow Prestwick Airport. While taxiing for departure from Runway 31, the commander was cleared to enter the runway via either holding point 'R1' or 'Q'. The pilot elected to use holding point 'Q' and positioned the aircraft on what he believed to be the runway centreline. After the first officer expressed concern regarding the aircraft's alignment, the crew taxied the aircraft further left until it was positioned directly over the runway edge lights.
As the takeoff roll commenced, the crew heard loud bumps originating from beneath the airframe. The commander immediately aborted the takeoff and requested permission to return to the stand. Upon inspection, airport authorities confirmed that five runway edge lights had been damaged. There were no injuries to the 3 crew members or 34 passengers on board, though the aircraft sustained damage to the nose gear uplock.
The investigation
The investigation examined the taxi procedures at Glasgow Prestwick, the lighting configuration of Runway 31, and the environmental conditions at the time of the incident. It was noted that the paved surface of Runway 31 is significantly wider than the declared runway width, extending 23 metres beyond each edge.
Investigators looked into the specific lighting at holding point 'Q', noting that unlike other taxiways, this entry point lacks green centreline lights, featuring only blue edge lights. The investigation also considered the impact of recent weather, specifically a heavy rain shower that occurred as the aircraft lined up, which may have affected the crew's visibility and depth perception.