What happened
The flight crew was cleared via radar vectors for a visual approach to runway 36. Prior to landing, the before-landing checklist was completed, and all aircraft systems were reported as operational. The DC-9 touched down on the 7,003-foot long concrete runway approximately 2,500 feet from the threshold.
During the landing roll, the first officer was operating the aircraft and applied normal braking; however, the airplane failed to decelerate as expected. Upon noticing the lack of deceleration, the captain took control of the flight controls and applied heavy braking, but there was still no noticeable reduction in speed. The aircraft continued rolling off the departure end of runway 36, eventually coming to a full stop in approximately one foot of mud.
Flight data recorder analysis showed a touchdown airspeed of 127 knots indicated airspeed, which matched the prescribed landing airspeed for the flight. The aircraft traveled 2,500 feet after touchdown and reached a complete stop 43 seconds later. While the crew reported a touchdown point of 2,500 feet from the threshold, a witness reported the touchdown occurred approximately 4,000 feet from the threshold. According to the aircraft operating manual, the target touchdown point is 1,000 feet from the runway threshold.
There were no injuries reported in this incident.