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The pilots of the very light jet were conducting a positioning flight in instrument meteorological conditions. The flight was cleared by air traffic control for the instrument landing system (ILS) approach; upon being cleared for landing, the tower controller reported to the crew that there was no standing water on the runway. Review of the airplane's flight data recorder (FDR) data revealed that the airplane reached 50 ft above touchdown zone elevation (TDZE) at an indicated airspeed of 118 knots (KIAS). The airplane crossed the runway displaced threshold about 112 KIAS, and it touched down on the runway at 104 KIAS with about a 7-knot tailwind. FDR data revealed that, about 1.6 seconds after touchdown of the main landing gear, the nose landing gear touched down and the pilot's brake pedal input increased, with intermediate oscillations, over a period of 7.5 seconds before reaching full pedal deflection. During this time, the airplane achieved its maximum wheel braking friction coefficient and deceleration. The cockpit voice recorder recorded both pilots express concern the that the airplane was not slowing. About 4 seconds after the airplane reached maximum deceleration, the pilot applied the emergency parking brake (EPB). Upon application of the EPB, the wheel speed dropped to zero and the airplane began to skid, which resulted in reverted-rubber hydroplaning, further decreasing the airplane's stopping performance. The airplane continued past the end of the runway, crossed a service road, and came to rest in a drainage ditch. Postaccident examination of the brake system and data downloaded from the brake control unit indicated that it functioned as commanded during the landing. The airplane was not equipped with thrust reversers or spoilers to aid in deceleration. The operator's standard operating procedures required pilots to conduct a go-around if the airspeed at 50 ft above TDZE exceeded 111 kts. Further, the landing distances published in the airplane flight manual (AFM) are based on the airplane slowing to its reference speed (Vref) of 101 KIAS at 50 ft over the runway threshold. The airplane's speed at that time exceeded Vref, which resulted in an increased runway distance required to stop; however, landing distance calculations performed in accordance with the AFM showed that the airplane should still have been able to stop on the available runway. An airplane performance study also showed that the airplane had adequate distance available on which to stop had the pilot continued to apply maximum braking rather than engage the EPB. The application of the EPB resulted in skidding, which increased the stopping distance. Although the runway was not contaminated with standing water at the time of the accident, the performance study revealed that the maximum wheel braking friction coefficient was significantly less than the values derived from the unfactored wet runway landing distances published in the AFM, and was more consistent with the AFM-provided landing distances for runways contaminated with standing water. Federal Aviation Administration Safety Alert for Operators (SAFO) 15009 warns operators that, "the advisory data for wet runway landings may not provide a safe stopping margin under all conditions" and advised them to assume "a braking action of medium or fair when computing time-of-arrival landing performance or [increase] the factor applied to the wet runway time-of-arrival landing performance data." It is likely that, based on the landing data in the AFM, the crew expected a faster rate of deceleration upon application of maximum braking; when that rate of deceleration was not achieved, the pilot chose to engage the EPB, which only further degraded the airplane's braking performance.

Following an uneventful flight, the flight crew briefed the arrival to the destination airport and set the calculated landing speeds. The captain and the first officer reported that during final approach, it felt like the airplane was “pushed up” as the wind shifted to a tailwind or updraft before landing near the runway number markings. Upon touchdown, the captain applied the brakes and thought that the initial braking was effective; however, he noticed the airplane was not slowing down. The captain applied maximum braking, and the airplane began to veer to the right; he was able to correct back to the runway centerline, but the airplane subsequently exited the departure end of the runway and traveled down a steep embankment. A pilot-rated passenger reported that throughout the approach to landing, he thought the airplane was high and thought that the excessive altitude continued through and into the base-to-final turn. He added that the bank angle of this turn seemed greater than 45 degrees. Recorded communication from the cockpit voice and data recorder (CVDR) revealed that during the approach to landing, the flight crew performed the landing checks, and the captain noted difficulty judging the approach. About 1 minute later, the recording revealed that the ground warning proximity system reported “five hundred” followed by a “sink rate, pull up” alert about 16 seconds later. Data from the CVDR revealed that about 23 seconds before weight-on-wheels was recorded, the airplane was at an indicated airspeed of about 124 knots and descending. The data showed that this approximate airspeed was maintained until about 3 seconds before weight-on-wheels. The recorded data further showed that the approach speed was set to 120 knots, and the landing reference speed (vREF) was set to 97 knots. Using the reported airplane configuration and the 3.5-knot headwind that was reported at the time of the approach and landing, calculations indicate that the vREF speed should have been about 101 knots indicated airspeed, which would have required a landing distance of about 3,112 feet. Utilizing the same airplane configuration and wind condition with the flight’s reported 124 knot indicated airspeed just before touchdown, the landing distance was calculated to be about 5,624 feet. The intended runway for landing was 5,132-feet long with a 1.9 percent downward slope gradient, and a 123-foot long overrun area. A postaccident examination of the airplane, including the braking system, revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. The pilot misjudged the airplane’s speed during the final approach, which resulted in runway overrun.