Primary finding
Probable cause
The glider pilot’s delayed decision to divert following a loss of thermal lift.
Investigator assessment
Analysis narrative
The pilot stated that his glider was towed to 3,000 feet above ground level (AGL) for a local soaring flight. He climbed the glider to 6,000 feet in a training area about 13 miles from the departure airport, where he "encountered sink." The pilot then obtained a landing clearance at an airport about 8 miles from his position, but the glider continued to sink, and struck an airport perimeter fence short of the landing runway. The off-airport landing resulted in substantial damage to the wings and fuselage structures. According to the glider's Pilot Operating Manual, the maximum glide ratio at maximum gross weight was 31:1. The pilot reported there were no pre-accident mechanical malfunctions or failures of the glider.
Source record
Factual narrative
The pilot stated that his glider was towed to 3,000 feet above ground level (AGL) for a local soaring flight. He climbed the glider to 6,000 feet in a training area about 13 miles from the departure airport, where he "encountered sink." The pilot then obtained a landing clearance at an airport about 8 miles from his position, but the glider continued to sink, and struck an airport perimeter fence short of the landing runway. The off-airport landing resulted in substantial damage to the wings and fuselage structures. According to the glider's Pilot Operating Manual, the maximum glide ratio at maximum gross weight was 31:1. The pilot reported there were no pre-accident mechanical malfunctions or failures of the glider.