Cessna 182K N2761Q accident near Cordova, Alaska

Probable cause

An encounter with mountain wave turbulence and windshear that exceeded the climb capability of the airplane and resulted in impact with terrain.

NTSB analysis

The pilot reported that, before departure, he reviewed weather conditions and proposed destination locations, which included winds aloft and METARs. About 2 hours and 15 minutes into the flight, at an altitude of about 12,500 mean sea level (msl), the airplane encountered severe turbulence and windshear, and, shortly thereafter, a downdraft. Unable to escape the downdraft, the pilot attempted to level the wings and pitched up. The airplane impacted mountainous terrain, resulting in substantial damage to the fuselage, wings, left horizontal stabilizer, and elevator. The pilot reported no preaccident mechanical failures or malfunctions that would have precluded normal operation.

Review of weather information revealed a relatively strong pressure gradient in the area. Upper air soundings indicated favorable conditions for severe mountain wave conditions with updraft and downdraft speeds between 2,000 and 3,000 ft per minute. Based on the available information, it is likely that the flight encountered mountain wave conditions, including severe turbulence, windshear, and downdrafts greater than 2,000 ft per minute, which exceeded the climb capability of the airplane and resulted in descent into terrain.

Text from the NTSB. Open the NTSB docket for ANC21LA043 for the full record.