What happened
During an approach to runway 30, the crew of a Bombardier Lear performed a landing under heavy rain conditions with an 8-knot tailwind. Although the aircraft was flying at the prescribed airspeed, the pilot elected to land on the 6,600-foot runway despite the tailwind. Upon touchdown, the pilot deployed the spoilers and applied the brakes, but noted a significant lack of deceleration. The aircraft's thrust reversers were non-operational due to previous maintenance actions.
As the aircraft continued its rollout on the wet surface, it failed to slow down sufficiently. By the time the aircraft reached the end of the runway, it was still traveling at an estimated speed between 85 and 9ered 90 knots. The aircraft exited the runway and traveled 618 feet into a rain-soaked grassy area. During this excursion, the nose gear collapsed after hitting a drainage swale, and the landing gear became partially embedded in the soft ground. There were zero fatalities and zero injuries reported.
Findings
Investigation into the accident revealed that the aircraft touched down beyond the intended touchdown zone, leaving approximately 600 feet less runway than the required performance calculations suggested for the wet conditions. The investigation identified that the aircraft experienced dynamic hydroplaning shortly after touchdown.
Furthermore, the anti-skid system was not performing optimally. Specifically, anomalies in the left main gear wheel speed sensors allowed the tires to enter a state of reverted rubber hydroplaning. This malfunction, combined with the heavy rain and the tailwind, significantly hindered the aircraft's ability to decelerate during the landing roll.