Weather (Other) · NTSB CEN09FA097

Hawker Beechcraft 58P — Stonewall, CO

2 fatal High-time pilotNight
DateDecember 21, 2008
LocationStonewall, CO
AircraftHawker Beechcraft 58P
Purpose of flightPersonal
ConditionsNight/Dark · Visual Meteorological Cond
Phase / occurrenceEnroute Other weather encounter
Pilot age67
Pilot total time1,634 hrs · Experienced
Time in type400 hrs
Fatalities2

Probable cause

The pilot's inadvertent flight into mountain wave activity resulting in a loss of control and subsequent impact with mountainous terrain.

NTSB findings

  • Environmental issues-Conditions/weather/phenomena-Wind-Downdraft-Effect on equipment - C

What happened

The pilot maneuvered the twin-engine pressurized airplane to a level attitude about 18,000 feet mean sea level (msl). Approximately 30 minutes later, while approaching the downwind side of a ridge of mountains, the airplane entered an uncontrolled descent and impacted mountainous terrain. During the last radio transmissions from the pilot, he reported having serious difficulties; however, he was unsure of the exact nature of the problem. Following the loss of radar contact, a pilot from a passing airplane approached the accident area and located the wreckage. As the pilot circled the wreckage, he encountered a mountain wave event and elected to depart the area. A meteorological study of weather conditions in the accident area indicated the potential for severe mountain wave activity at the time of the accident. There were also numerous pilot reports specifically identifying encounters with mountain waves and/or severe or extreme turbulence at flight levels close to the accident area. A postaccident examination of the airplane revealed no anomalies that would have precluded normal operation.

An editorial "what led to it / how to avoid it" analysis for this accident is generated separately and will appear here.

View the official NTSB docket →