Sportine Aviacija LAK17 N290MH accident near Lake Port, California

Probable cause

The pilot’s exceedance of the glider’s critical angle of attack during flight, which resulted in an aerodynamic stall and subsequent impact with terrain.

NTSB analysis

The pilot departed on a local flight in his newly purchased self-launching motorglider in day visual meteorological conditions. Flight track data showed the glider complete multiple turns in the vicinity of the airport at various altitudes. About 20 minutes into the flight, flight track data ended near the accident site. The end of the data showed the glider in a short, steep climb before turning left and losing about 70 ft of altitude. The final data point showed the glider about 564 ft above ground level. There were no witnesses to the accident. Although the recorded data did not capture engine operation for the accident flight, examination of the wreckage indicated that the engine was operating at the time of impact.

The pilot had over 1,600 hours of flight experience in gliders and about 4.5 hours in the accident glider. Although the flight track data did not show an aerodynamic stall causing the glider to descend to the ground, it is likely that one occurred. According to photos supplied by first responders, the glider was found in multiple sections scattered within about a 100 ft radius. In the immediate vicinity of the debris field and wreckage, trees and bushes were not damaged indicating that the glider was most likely in a nose low descent at the time of impact.

Text from the NTSB. Open the NTSB docket for WPR20LA257 for the full record.