What happened
On 24 November 2014, a Gulfstream III, registration N103CD, was prepared for a private flight from Biggin Hill Airport to Canada. During the taxi from Holding Point J1, the aircraft moved through patches of low-level fog. As the crew lined up for departure on Runway 03, they mistakenly identified a line of runway edge lights as the runway centerline.
The aircraft began its takeoff roll at 2030 hrs, but instead of remaining on the runway, it traveled approximately 248 meters on the paved surface before running onto the grass. The commander immediately closed the thrust levers to reject the takeoff. The aircraft sustained major structural damage, including a hole in the fuselage and the separation of the nose landing gear, and was subsequently declared damaged beyond economic repair. There were no fatalities and no injuries among the two crew members and five passengers.
The investigation
The AAIB investigation examined the aircraft's path, the aerodrome lighting, and the information available to the crew. Evidence from GPS-enabled tablets and CCTV confirmed the aircraft's trajectory. The investigation found that the crew's mental model of the taxi route was incorrect due to the lack of specific information on their electronic charts.
Investigators also analyzed the lighting environment, noting that the presence of fog caused a 'halo effect' around bright lights, which degraded the crew's ability to perceive the true nature of the lighting. Furthermore, the investigation highlighted that the authoritative UK AIP contained warnings about the runway's extra width and lack of centerline lighting, but this critical information was absent from the commercial charts used by the crew.
Findings
- The crew developed an incorrect mental model of the taxi route from the holding point to the runway.
- The crew misidentified runway edge lights as centerline lights, which reinforced their incorrect positioning.
- Environmental factors, including night operations, patchy fog, and the presence of an Operational Readiness Platform (extra pavement), provided misleading visual cues.
- The absence of runway centerline lighting at Biggin Hill made it difficult to verify correct alignment.
- Critical safety information regarding the runway width and alignment was missing from the crew's iPad aerodrome charts.
Safety action
Following the accident, Biggin Hill Airport implemented temporary measures, including the installation of reflective studs and blue taxiway edge markers to better delineate taxiways and runway access points. The chart supplier also updated its Biggin Hill Airport Diagram Chart to include the necessary alignment warnings.