What happened
On 27 February 2007, at approximately 06:20, a Boeing 737-600, registration LN-RPA, operating as flight SK001, departed from Luleå/Kallax airport using the wrong runway. The flight was scheduled to travel to Stockholm/Arlanda.
Prior to departure, the crew had programmed the aircraft's flight management system for runway 32 based on initial information received from air traffic control. During taxiing toward the de-icing ramp, the air traffic control officer (ATCO) suggested the use of runway 14 for takeoff instead. However, due to simultaneous radio communications and telephone activity, the crew's response to this suggestion was unclear.
As the aircraft proceeded, visibility at the airport significantly deteriorated due to snow, making it impossible for the ATCO to visually monitor the aircraft. While the ATCO provided clearance for runway 14, the crew taxied toward runway 32. Despite the discrepancy, the crew notified the tower they were ready for takeoff at the full length of runway 14, and the ATCO issued the takeoff clearance for runway 14. The aircraft subsequently departed from runway 32.
The investigation
The Swedish Accident Investigation Board (SHK) examined the sequence of events, focusing on the interaction between the flight crew and air traffic control. The investigation reviewed the aircraft's performance calculations, which included multiple variations for both runway 14 and runway 32.
The investigators also analyzed the ATCO's communications and the environmental conditions. The investigation noted that the ATCO was managing multiple tasks, including telephone calls regarding slot time management and coordinating with ground services. The investigation was partially limited because the cockpit voice recordings from the time of the incident had been overwritten before they could be secured.
Findings
- The flight crew failed to maintain effective Crew Resource Management (CRM), specifically regarding internal and external communications during the takeoff phase.
- The ATCO was managing high-pressure situations, including slot time constraints and simultaneous telephone communications, which contributed to the confusion.
- The similarity in the naming conventions of the Standard Instrument Departures (SIDs) for the two runways increased the risk of confusion.
- Reduced visibility prevented the ATCO from visually confirming the aircraft's actual position on the taxiway.
Safety action
The investigation highlighted several areas for potential improvement, including the need to develop a system for naming SIDs that minimizes the risk of confusion. Additionally, the report suggested reviewing airport signage for takeoff positions and investigating the implementation of systems that would allow air traffic controllers to more accurately determine an aircraft's position during low-visibility operations.