What happened
On July 21, 2004, a B737-800, registration EI-CSA, was operating a scheduled passenger service from London Stansted to Skavsta Airport, Sweden. During the descent phase, the pilot flying failed to transition the aircraft from cruise level to descent mode, maintaining an altitude hold well past the top of descent.
As the aircraft approached the runway, the flight crew attempted to recover the profile by increasing the rate of descent. This maneuver resulted in a nose-down pitch of over 10 degrees and a significant increase in airspeed, reaching approximately 2/70 kt. Due to the excessive speed, the crew could only extend the flaps to position 10, rather than the standard landing configuration of 30. The aircraft eventually touched down at a speed of roughly 180 kt, which was approximately 40 kt above the normal parameters. Despite the high-speed impact, the aircraft remained within the landing distance and no injuries were reported among the 184 passengers or 6 crew members.
The investigation
The AAIU investigation focused on the breakdown of standard operating procedures (SOPs) and Crew Resource Management (CRM) during the final fifteen minutes of the flight. Investigators examined flight data, which revealed excessive rates of descent reaching 6,200 fpm and Ground Proximity Warning System (GPWS) alarms that went unaddressed by the pilot flying.
The investigation also looked into the pilot's personal circumstances. The pilot flying admitted to experiencing significant physiological and psychological fatigue stemming from ongoing marital difficulties and the stress of a recent family separation. He acknowledged that his concentration was compromised, leading to a fixation on the runway that caused him to ignore the warnings and inputs from the first officer.
Findings
- The primary cause of the incident was the aberrant behavior of the pilot flying, who disregarded SOPs and CRM protocols due to accumulated personal stress and fatigue.
- The first officer was unable to effectively counteract the pilot's actions due to the steep experience gradient between the two crew members.
- The pilot flying failed to initiate the descent at the appropriate time, leading to an unstable approach.
- The crew did not report the structural limit exceedances or the high-speed approach to the operator's technical logs or operations department.
- The loss of ATC audio tapes at Skavsta Airport hindered the investigation's ability to review cockpit communications.