Amateur-built ASC SPIRIT N127JK accident near Lehi, Utah

Probable cause

The pilot’s exceedance of the glider’s critical angle of attack while maneuvering in a steep turn at low altitude, which resulted in an aerodynamic stall.

NTSB analysis

The private pilot of the experimental, amateur-built glider was conducting a local flight. The tow plane pilot reported that, as the glider pilot approached the privately owned airport, he announced over the radio his intent to land. He and one witness in the area reported seeing the glider circling to land and making several steep turns during the descent. When the glider was about 30 to 40 ft above ground level, the nose suddenly dropped, and the glider then descended straight down into the ground short of the runway. Another witness reported that it looked like the glider had stalled.

Wreckage documentation indicated that the glider impacted terrain in a steep, nose-down, left-wing-low attitude with little forward motion, which is consistent with a stall. Postaccident examination of the airframe revealed no anomalies that would have precluded normal operation. It is likely that the pilot exceeded the glider's critical angle of attack while maneuvering to land, which resulted in an aerodynamic stall.

Text from the NTSB. Open the NTSB docket for WPR14LA263 for the full record.