What happened
On June 6, 2004, a Lufthansa CityLine Avro RJ85 was taxiing at Bergen Airport Flesland, Norway, after receiving clearance to proceed to a holding position on taxiway A. During the taxi sequence, a Braathes Boeing 737-505, registered LN-BRH, was performing a visual approach for runway 17 and had been cleared to land by the tower controller.
As the Lufthansa crew approached the holding position, they transitioned from ground control to tower frequency but failed to check in with the tower. Simultaneously, the ground controller observed the Avro RJ85 crossing the holding position line and entering the active runway. The ground controller immediately alerted the tower controller, who subsequently revoked the landing clearance for the arriving Boeing 737-505 and instructed the pilot to extend the approach. The Lufthansa aircraft halted on the runway, blocking traffic, which forced the tower to reorder the sequence and grant takeoff clearance to the stationary aircraft before the Braathens flight could land.
The investigation
The Norwegian Safety Investigation Authority (AIB-N) examined radio transcripts, controller reports, and pilot statements. The investigation focused on the cockpit environment during the taxi, the visibility of runway markings, and the accuracy of aerodrome charts. Investigators noted that the crew was managing high workload, including reviewing checklists and receiving cabin clearance, which contributed to a loss of situational awareness.
Findings
- The primary cause of the incursion was cockpit workload and a lack of situational awareness regarding the aircraft's position relative to the holding markings.
- The crew experienced confusion at the intersection of taxiway A and Y due to the complex layout and the fact that the aerodrome chart did not clearly depict the taxiway leading to the military apron.
- There was a physical misalignment between the painted holding position markings and the taxiway signage on taxiway A, with signs being offset from the painted lines.
- The angle of taxiway A's intersection with the runway (approximately 60 degrees) provided a sub-optimal view of the final approach for pilots.
Safety action
- The AIB-N recommended that the airport operator, Avinor AS, review the placement of holding position markings and signs on taxiway A and consider additional signage on taxiway Y.
- The AIB-N recommended that the Aeronautical Information Service of Norway revise aerodrome charts for airports with military installations to ensure all available taxiways and intersections are clearly depicted.