What happened
On April 11, 1997, at 01:54 local time, a Douglas DC-9-83 (MD-83), registration TC-INC, operated by Intersun Sunways, experienced a runway excursion at Joensuu Airport, Finland. The aircraft was operating flight SWW 1022 from Jyväskili to Joensuu, with 167 passengers and a crew of six on board.
During the landing phase, the aircraft failed to stop on the runway. The aircraft initially came to a halt on a gravel surface covered with 15–20 cm of hard snow, approximately 40 meters past the runway end. Flight data and passenger statements indicate that the crew attempted to use engine thrust three times to taxi the aircraft back onto the runway, eventually coming to a final stop 60 meters beyond the runway end.
While the aircraft sustained no significant damage and no fire occurred, the incident created a dangerous situation during the evacuation. Passengers were transferred to buses across the snowy terrain in the dark without proper crew guidance. One passenger sustained a minor injury during the disembarkation process.
The investigation
The investigation examined the flight crew's training, the aircraft's technical systems, and the operational procedures of Intersun Sunways. Investigators analyzed the flight recorder (UFDR) data, which played a critical role in establishing the sequence of events, including the unauthorized use of engine thrust after the initial stop.
The investigation also reviewed the airline's training programs, noting discrepancies in simulator training and winter operations training. Additionally, the oversight role of the Turkish Directorate General of Civil Aviation (DGCA) was scrutinized, alongside the adequacy of the airport's emergency response and the crew's adherence to the Flight Crew Operating Manual (FCOM).
Findings
- The primary cause of the excursion was the inadequate winter operations skills and knowledge of the flight crew. The captain's braking technique, specifically the use of wheel brakes and engine thrust, deviated from the established FCOM procedures.
- The first officer failed to effectively monitor the landing, specifically failing to verify the deployment of spoilers.
- The airline, Intersun Sunways, failed to ensure the crew's proficiency, providing insufficient simulator training and inadequate winter operations training without proper follow-up.
- The Turkish DGCA failed to provide adequate oversight of the new charter operator's operations.
- There were significant operational deficiencies, including errors in flight documentation, improper use of checklists, and the crew's limited proficiency in English.