Dg Flugzeugbau Gmbh DG 1000S N767SS accident near Lake Chelan, Washington

Probable cause

The glider’s encounter with atmospheric conditions where the lift was not sufficient to maintain flight. Contributing to the accident was the pilot’s decision to overfly a suitable landing site which resulted in an off-field landing in a lake.

NTSB analysis

The pilot reported he was soaring when he penetrated two areas of “heavy sink” before reaching the final wave lift of the flight that took him to 16,500 ft. When he left the wave lift the glider began to sink and he quickly focused on regaining lift and did not think about the final glide back to the departure airport. The pilot subsequently overflew a suitable alternative airport as he continued to search for lift while the glider continued to sink at about 1,000 ft per minute. The pilot eventually maneuvered into a position where his best option was to land in a lake when he could not find sufficient lift or return to an airport. Both wings were substantially damaged when the pilot landed in the lake. The pilot reported that there were no preaccident mechanical malfunctions or failures with the glider that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR22LA223 for the full record.