Incident Overview
Before landing, the flight crew was advised that the braking action on the runway was reported as 'fair,' and they acknowledged this advisory. After touchdown, the first officer selected reverse thrust to slow the airplane. The crew then noticed that the airplane was not slowing at a normal rate. The captain assumed control of the airplane and applied maximum braking and reverse thrust; however, the airplane continued off the departure end of the runway.
Post-Incident Measurements and Data
Measurements taken immediately after the incident indicated that the braking action for the runway was 38 (fair), 23 (poor), and 27 (poor). Review of the flight data recorder revealed that the spoilers remained retracted at touchdown and during rollout to zero airspeed.
Relevant Manual Guidance
According to the MD-80 Flight Crew Operating Manual, 'When armed, the automatic brake system (ABS) will automatically apply brakes during landing and takeoff modes of flight. ABS landing mode is activated when spoilers are deployed either automatically or manually.' The Abnormal Flight Profiles section of the Pilots Reference Manual stated, 'Ground spoilers significantly increase brake effectiveness. In order to achieve a maximum performance stop, ensure that ground spoilers have extended.'
Checklist Duties
Review of the Delta Airlines MD-80/90 Normal Checklist revealed that it was the duty of the 'pilot not flying' to ensure that spoilers were in the 'ARM' position.