WPR10LA377 · Glaser Dirks DG300

The accident pilot and a second glider pilot were operating in the same area about 7,400 feet mean sea level (msl). The accident pilot informed the second pilot over the radio frequency that he was climbing between 300 to 500 feet per minute (fpm). About an hour later, the second pilot learned from another pilot at the departure airport that the accident pilot had not returned. A subsequent search over the area resulted in the second pilot spotting the wreckage in a canyon about 6 nautical miles southeast of the departure airport. Track-log data recovered from an onboard recording device revealed that, after takeoff, the glider ascended to an altitude of about 9,100 feet msl during the first eight minutes of the flight. Additionally, the track-log data showed that about 28 minutes into the flight, at an altitude of 8,800 feet msl, the glider began a progressive descent, which lasted about 15 minutes until the glider impacted remote mountainous terrain at an elevation of about 6,500 feet msl. During the last 2 minutes of the flight, the ground speed fluctuated twice over a 15-knot range and was at 40 knots just before the altitude dropped abruptly and the glider descended vertically to the ground elevation in the last 12 seconds. A postaccident examination of the accident site revealed the entire glider was located in the general area where the impact occurred, there was no linear distribution path, and no indication of an in-flight breakup. The trees surrounding the accident site were not disturbed and the glider impacted the terrain in a steep angle, consistent with a stall/spin. No anomalies were noted with the glider that would have precluded normal operation.

Verbatim NTSB analysis and probable cause from the NTSB dataset