What happened
During a night landing on a 5,000-foot asphalt runway, the pilot attempted to land the aircraft on a wet surface under calm wind conditions. The pilot reported touching down before the 1,000-foot markers and immediately applied maximum braking pressure. While the anti-skid system began cycling, the pilot noted the response felt slower than usual. During the landing roll, the left brake suddenly grabbed, causing the aircraft to yaw left and enter a series of lateral skids. The aircraft eventually exited the runway, traveled down an embankment, and struck a rocky berm approximately 360 feet beyond the runway end. All occupants, including the pilot and passengers, exited the aircraft without injury, though a fire broke out following the impact and destroyed the cockpit, the right wing, and the center fuselage.
Findings
Investigation into the flight data was limited because thermal damage from the fire destroyed the avionics. However, ADS-B data confirmed the aircraft was on final approach at a ground speed of 120 knots, which matched the pilot's report. While the pilot used the cockpit display unit (CDU) to calculate a landing reference speed (Vref) of 120 knots, simulations using the actual environmental conditions showed that the correct Vref should have been 112 knots. Furthermore, calculations indicated that a landing at 120 knots on the wet runway would require a distance exceeding the available 5,000 feet. Specifically, a speed of 117 knots would have required 5,311 feet, and 122 knots would have required 5,794 feet. The CDU had been programmed with the runway length and would have displayed a warning that the landing field length was insufficient for those speeds.
Regarding the braking system, no mechanical failures were found that would have prevented normal operation. Although a testing anomaly involving hysteresis was noted in the power brake and anti-skid valve, the manufacturer stated this would not prevent braking or pressure release. Ultimately, the investigation concluded that the pilot landed the aircraft at a speed higher than required for the available runway length.