What happened
On June 23, 1999, an SAS Norge Douglas DC-9-82 (registration LN-RLF) was operating a scheduled passenger flight from Stockholm/Arlanda to Växly/Kronoberg airport. The weather at the time of arrival featured rain showers in the area and a wet runway.
Upon touchdown on runway 19, the crew utilized engine reverse thrust to decelerate. While the initial deceleration appeared normal, the pilot in the left seat eventually noticed a lack of sufficient retardation. In an attempt to stop the aircraft, the pilot rechecked the automatic brake system (ABS) settings, increased reverse thrust, and eventually set the ABS to the maximum position. Despite these efforts, the aircraft could not stop within the remaining runway distance and exited the pavement, coming to a halt approximately 41 meters beyond the runway edge at a speed of 10-20 knots. There were no injuries among the 125 people on board.
The investigation
The Swedish Accident Investigation Authority (SHK) examined the aircraft's flight recorders and technical systems. The investigation revealed that while the aircraft was mechanically sound, the landing spoilers had not deployed. Because the spoilers were not deployed, the automatic braking system (ABS) was never activated.
The investigation also noted that the crew's cockpit composition—two highly experienced commanders, with the more senior acting as the first officer—can present specific risk factors. Furthermore, the crew failed to stop the cockpit voice recorder (CVR) after the incident, which resulted in the loss of the initial landing audio data.
Findings
- The aircraft spoilers were not armed prior to landing.
- Because the spoilers failed to deploy, no wheel braking occurred during the rollout.
- The aircraft relied solely on engine reverse thrust for deceleration.
- A breakdown in Crew Resource Management (CRM) prevented the proper execution of the landing checklist, specifically the arming of the spoilers.
- The first officer failed to visually confirm the lack of spoiler deployment and did not verbally notify the commander after touchdown.
- The aircraft design lacks a warning system to alert pilots if the spoilers are not armed for landing, unlike the warning provided during the takeoff phase.