Cessna 680 N606CS accident near Eagle, Colorado

Probable cause

The airplane’s encounter with localized severe to extreme mountain wave turbulence which resulted in substantial damage to both wings.

NTSB analysis

The airplane encountered extreme turbulence after leveling from a climb at 18,000 feet. The extreme turbulence encounter caused a brief loss of control that lasted less than a minute. The airplane then made an uneventful descent and landing. A postflight inspection of the airplane revealed overstress damage that caused wrinkling and debonding on both wings. The synoptic surface weather chart for the flight identified an area of high pressure to the west and an area of low pressure to the east. These conditions were conducive to mountain wave turbulence. An inflight weather advisory was in effect for moderate turbulence, icing, and mountain obscuration for the accident location and altitude. Low-level significant weather charts advised of moderate or greater turbulence below 20,000 feet for the accident region. Pilot reports in the area near the time of the turbulence event indicated moderate levels of turbulence above 10,000 feet. The preflight weather information obtained by the flight crew did not include available information about the turbulence forecasts or the pilot reports of turbulence.

Text from the NTSB. Open the NTSB docket for CEN10LA204 for the full record.