What happened
On 17 September 2003, a BAe Jetstream 32, registration SE-LNT, was performing a scheduled flight from Pajala to Luleå/Kallax Airport. The flight was being used as a training opportunity for the co-pilot, as there were no passengers on board. The commander decided to simulate an engine failure to provide flight experience.
During the approach to Luleå, the commander reduced thrust on the right engine to a very low level, intending to simulate a feathered engine. While the commander planned to restore normal thrust before touchdown, the co-pilot believed the entire landing would be conducted with one engine at reduced thrust. As the aircraft crossed the runway threshold, the right engine thrust had dropped to approximately 7%.
Shortly after crossing the threshold, at an altitude of roughly 5 meters, the aircraft experienced a sudden yaw and roll to the right. Despite the crew applying full rudder and aileron, the motion became uncontrollable. The right wingtip struck the ground, causing the aircraft to slide on its belly for approximately 50 meters. The co-pilot sustained minor injuries to one leg, and the aircraft was substantially damaged.
The investigation
The Swedish Accident Investigation Board (SHK) examined the aircraft's flight data, cockpit voice recordings, and the technical state of the left aileron. The investigation also reviewed the company's operational manuals and the pilots' training backgrounds. Investigators analyzed the thrust levels recorded by the Flight Data Recorder (FDR) and the crew's communication during the approach. The investigation also looked into the commander's qualifications and the company's oversight of flight training procedures.
Findings
- The primary cause of the accident was a lack of coordination and communication regarding the intended thrust settings during the simulated failure.
- The commander was acting as a flight instructor for a specific aircraft type without being officially authorized or certified as an instructor for that type in the company's manual.
- The pilots lacked sufficient knowledge regarding the specific flight characteristics of the BAe Jetstream 32 when operating under asymmetrical thrust conditions.
- There were significant shortcomings in the operator's quality control system, including inadequate regulations for flight training and insufficient supervision of pilot training routines.