What happened
The accident occurred while the aircraft was conducting an instrument landing system (ILS) approach to runway 24, which measures 6,400 feet in length. Visual contact with the runway surface was established at approximately 500 feet above ground level, at which point the aircraft was indicating one dot high on the glide slope. Witnesses reported that the aircraft touched down past the halfway point of the runway while configured with full flaps during moderate rain conditions.
At the time of touchdown, a 5-knot tailwind was present, and the runway featured a 0.8% downslope. Upon application of the brakes, the pilot found them ineffective and called for the flaps to be raised. Despite this adjustment, braking remained ineffective. Consequently, the pilot elected to ground loop the aircraft in an attempt to stop it.
Investigation revealed left-turning skid marks starting 300 feet before the end of the runway. These marks continued 120 feet beyond the runway limit until the aircraft traveled off an embankment. Approximately three inches of water was present on the runway surface at the time of the accident. The aircraft traveled another 120 feet beyond the embankment before colliding with upsloping terrain on the other side.
The investigation
Examination of the scene confirmed the sequence of events described by witnesses and physical evidence. The presence of moderate rain and standing water contributed to reduced friction. The runway's downslope and the tailwind component increased the ground speed and distance required to stop. The pilot's attempt to raise flaps while maintaining braking pressure did not restore sufficient deceleration capability.
Findings
Contributing factors included the wet runway conditions, the presence of standing water, the tailwind, and the runway downslope. The ineffective braking was a critical factor in the inability to stop within the available distance. The decision to ground loop was made as a last-resort measure to arrest forward momentum but resulted in the aircraft leaving the paved surface.
Safety message
Pilots should be aware that landing on wet runways with tailwinds and downslopes significantly increases stopping distances. Braking effectiveness can be severely compromised by standing water, requiring careful consideration of available runway length and weather conditions during approach planning.