Raytheon Aircraft Company HAWKER 800XP N99AP accident near Aspen, Colorado

Probable cause

The flight crew’s decision to takeoff in tailwind conditions that were consistently above the airplane’s tailwind limitation, which resulted in a runway overrun following an aborted takeoff. Contributing was the flight crew’s use of the instantaneous wind report for the decision to attempt the takeoff.

NTSB analysis

The flight crew of the business jet was conducting a cross-country flight. Before departure, the airplane and runway were clear of any contaminants, all pre-takeoff checks were normal, and the flaps were set to 15° to reduce the takeoff length. At the time the airplane was cleared to taxi to the departure runway, the reported wind was from 170° at 18 knots (kts) and gusting to 30 kts. This wind report represented a prevailing tailwind that exceeded the airplane’s takeoff and landing maximum tailwind limitation, which was 10 kts. About 30 minutes later due to arrival traffic, air traffic control (ATC) provided the takeoff clearance and reported the wind was from 160° at 16 kts, gusting to 25 kts, and the “instantaneous wind” was from 180° at 10 kts. Following the accident, the captain reported that “at takeoff clearance; constant winds were reported by tower at [180° at 10 kts] which was within aircraft maximum tailwind takeoff limitation.”

About 30 seconds after receiving the takeoff clearance and the current wind report from ATC, the captain performed a static takeoff, which began at the end of the runway, and the first officer made all the callouts. According to the captain, at rotation speed (VR), he applied back pressure on the yoke; however, the airplane would not become airborne. After a few seconds without any indication the airplane would take off, the captain called for and performed an aborted the takeoff. The captain reduced the engines to idle, deployed the thrust reversers, and applied the brakes. The airplane subsequently departed the end of the runway into the snow and sustained substantial damage to the right wing and fuselage.

Because postaccident examination of the airplane and flight control system found no anomalies, and findings from an airplane performance study indicate that the airplane should have been able to rotate once it reached the reported VR, it is very likely that the airspeed did not reach VR due to tailwind conditions that exceeded the airplane’s maximum tailwind limitation. The airplane was not equipped with a flight data recorder or any additional data sources that could have captured or reported the airplane’s airspeed during the attempted takeoff.

Although the flight crew received an unsolicited instantaneous wind report from ATC that was at the airplane’s maximum allowable tailwind component of 10 kts, multiple wind reports for 30 minutes before the attempted takeoff were significantly above the tailwind limitation. The flight crew failed to consider the wind conditions that were consistently above the maximum tailwind limitation and decided to attempt the takeoff once they received an instantaneous wind report that did not exceed the tailwind limitation. Per the flight crew statements, they interpreted the instantaneous wind reported by ATC just before takeoff as the constant wind conditions.

The term ”instantaneous wind” is used by the airport’s ATC tower and is not defined in any Federal Aviation Administration publication. Because the ambiguous term is not defined in available resources, pilots that infrequently operate at that airport are likely not familiar with the definition and potential operational impact.

Text from the NTSB. Open the NTSB docket for CEN22LA130 for the full record.