Introduction
An aircraft overran the departure end of a runway during landing after an unstabilized approach. The accident was investigated, and the probable cause was attributed to the pilots' unstabilized approach and excessive airspeed.
Flight and Approach
Following an uneventful flight, the flight crew briefed the arrival and set calculated landing speeds. During final approach, both pilots reported feeling the airplane "pushed up" as the wind shifted to a tailwind or updraft before touchdown near the runway number markings. A pilot-rated passenger observed that the airplane appeared high throughout the approach and that the bank angle during the base-to-final turn seemed greater than 45 degrees.
Cockpit voice and data recorder (CVDR) recordings indicated that the flight crew performed landing checks, and the captain noted difficulty judging the approach. About one minute later, the ground warning proximity system reported "five hundred" followed by a "sink rate, pull up" alert approximately 16 seconds later. Data showed that about 23 seconds before weight-on-wheels, the aircraft was at an indicated airspeed of about 124 knots and descending, maintaining that approximate airspeed until about three seconds before touchdown.
The recorded approach speed was set to 120 knots, with a landing reference speed (VREF) of 97 knots. Using the reported airplane configuration and the 3.5-knot headwind at the time, calculations indicated that the proper VREF should have been about 101 knots indicated airspeed, requiring a landing distance of approximately 3,112 feet. However, at the actual 124-knot indicated airspeed just before touchdown, the calculated landing distance was about 5,624 feet.
Landing and Runway Overrun
Upon touchdown, the captain applied brakes and initially thought braking was effective, but noticed the airplane was not slowing. He applied maximum braking, causing the airplane to veer right; he corrected back to the centerline, but the aircraft subsequently exited the departure end of the runway and traveled down a steep embankment. The intended runway was 5,132 feet long with a 1.9 percent downward slope gradient and a 123-foot overrun area.
Investigation Findings
A post-accident examination of the airplane, including the braking system, revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The investigation determined that the pilot misjudged the airplane's speed during the final approach, which resulted in a runway overrun.
Probable Cause
The probable cause of the accident was the pilots’ unstabilized approach and excessive airspeed during approach, which resulted in an insufficient landing distance to stop the airplane before overrunning the runway.