ERA20LA145

According to the tow pilot, while climbing through about 500 ft above the ground during takeoff, they encountered an area of turbulence and the glider got “low on the tow” and out of view in his mirror. He then felt the glider release from the tow. Witnesses stated that the glider released from the tow at "low" altitude and turned back toward the gliderport when the nose of the glider pointed “down," and the glider descended vertically from view. Examination of the wreckage confirmed continuity to all flight control surfaces and revealed no preimpact mechanical anomalies. Review of the pilot’s logbook revealed a total of 49 flights. Of those flights, 44 were performed in two-seat gliders. The pilot had recorded five flights in the accident glider, all of which included an aerotow to a release altitude of either 2,500 or 3,000 ft agl. There was no evidence to indicate that the pilot had performed any simulated takeoff emergencies in the accident glider make and model. A number of different mechanical, operational, and environmental factors can result in an early termination of a tow; however, the reason the pilot terminated the tow could not be determined based on available evidence. Witness descriptions of the glider’s flight after release are consistent with the pilot exceeding the critical angle of attack while maneuvering toward the runway, which resulted in an aerodynamic stall.

On April 7, 2020, at 1400 eastern daylight time, a Schempp-Hirth Standard Cirrus glider, N271BL, was substantially damaged when it was involved in an accident near Groveland, Florida. The private pilot was fatally injured. The glider was operated as a 14 Code of Federal Regulations Part 91 personal flight. According to the tow pilot, it was customary to tow gliders to 2,000 ft above ground level (agl) before tow release. He said that the initial takeoff from runway 36 was "…normal with slight PIOs (pilot-induced oscillations) from the glider but nothing extreme.” About 500 ft above the ground, the aircraft encountered an area of turbulence, and the tow pilot noticed that the glider was low and out of sight in his mirror. At that time, he felt the glider release from tow. The tow pilot did not witness the glider's descent or the accident. He added that at no time did he see the glider’s spoilers deployed. Two witnesses on the ground, who were residents of the gliderport residential community, described watching the glider release from the tow at a "low" altitude and turn to the east. They each described the turn continuing to the south, and then the nose of the glider "point down," before it descended vertically from view. The glider came to rest on the gliderport property behind a residence on the east side of the turf runway. Postaccident examination of the wreckage confirmed flight continuity to all flight control surfaces and revealed no preimpact mechanical anomalies. An officer with the parent company of the gliderport was familiar with the glider and said that another pilot had recently flown it in competition; the glider was not disassembled after the competition but was hangered fully assembled. Flight control checks were performed and "certified" on the glider prior to the competition. Three devices (LXNav Nano, Naviter Oudie, and Nadler SN10) used for gliding and free-flight events and capable of storing non-volatile memory, were harvested from the wreckage; however, no data was recovered from the devices. Review of the pilot’s logbook revealed a total of 49 flights. Of those flights, 44 were performed in two-seat gliders. The pilot had recorded five flights in the accident glider, all of which included an aerotow to a release altitude of either 2,500 or 3,000 ft agl. There was no evidence to indicate that the pilot had performed any simulated takeoff emergencies in the accident glider make and model. According to the Soaring Society of America Soaring Safety Foundation, premature terminations of the tow are a leading cause of glider accidents and pilot fatalities. These events include not only broken towlines, but any event that involves a significant level of distraction for the pilot, such as inadvertent extension of the spoilers/dive brakes during takeoff or climb; an improperly closed or locked canopy; mechanical occurrences; and the pilot’s failure to maintain a proper position behind the tow plane.