History of Flight
On August 29, 2018, about 1200 eastern daylight time, a Schweizer SGS 2-32 glider, registered N17970, was substantially damaged when it crashed near Morristown, Vermont. The pilot and two passengers were fatally injured. The glider was operated as a Title 14 Code of Federal Regulations Part 91 local sightseeing flight.
According to the tow pilot, the flight was intended to provide a 30-minute sightseeing tour to two passengers in the 3-place glider. After takeoff, the tow pilot climbed to 4,500 ft mean sea level, where the glider pilot released. The glider turned westbound toward Spruce Creek and Sterling Pond. The tow pilot returned to the airport and did not visually monitor the glider.
A witness hiking near Sterling Pond saw the tow plane and glider in flight and photographed them. The witness reported that the tow plane made a "slingshot" turn and the glider released, then flew away and "disappeared" into the clouds.
When the glider had not returned after 45 minutes, the tow pilot attempted radio contact without success. After multiple attempts, airport personnel notified local 911, and an FAA Alert Notice was issued. The tow pilot and another local pilot began an aerial search; at 1756, the glider was spotted near the summit of Sterling Mountain. At 2135, search and rescue crews reached the accident site, about 40 ft below the summit at an elevation of 3,673 ft msl, 7 miles from the departure airport on a 297° ground track.
Personnel and Aircraft Information
The pilot owned the sightseeing company. His logbooks showed 1,214 hours of glider experience, including 406 hours in the accident glider make and model.
The maximum allowable gross weight for the glider in the utility category was 1,430 lbs. The center of gravity (CG) range was 101.08 to 105.18 inches aft of datum. The computed weight and balance for the accident flight indicated the glider weighed 1,480 lbs, with a CG at 101.63 inches aft of datum, approaching the forward limit.
According to the glider type certificate holder, the glider was certified with lap belts and shoulder harnesses at all seating positions. In May 2018, the pilot was advised during an annual inspection of another identical glider that proper seat belts and shoulder harnesses were required, as the installed belts were not original or approved replacements. The pilot agreed and purchased an additional set of seat belts and shoulder harnesses for the accident glider, picking them up on June 27, 2018.
Meteorological Information
The tow pilot checked winds on two commercial websites before the flight. Winds aloft at Plattsburg, New York (about 40 miles away) were reported at 37 knots from the southwest on one site, while another site indicated winds aloft of 16 knots at 1,000 ft above ground level over Morristown. The tow pilot thought the discrepancy was unusual.
During the climb and release, the tow pilot said the air was "really smooth," but he had to "weave around the clouds" with "plenty of room" between them. Some mountaintops were partially obscured. The glider pilot typically checked weather before a flight and "liked to run the ridge on the Burlington (west) side, and the clouds were hard to see."
The atmospheric conditions at the time were conducive to instrument meteorological conditions. A weather research and forecasting model indicated cloudy conditions with bases around 3,700 ft msl, downdrafts of 100 to 300 ft per minute, and horizontal wind magnitudes of 25 knots or greater possible amongst the terrain.
Wreckage and Impact Information
All major components were accounted for at the accident site. The glider came to rest in a near-vertical, nose-down attitude. The nose and left wing leading edge rested on the ground. The left wing was torn about 9 ft inboard of the tip but remained attached by sheet metal and control tubes. The right wing was attached and bowed slightly between aileron attach points. The empennage was wrinkled on the left side just aft of the wing; the vertical stabilizer, rudder, horizontal stabilizer, and elevator were intact. Flight control continuity was confirmed from the cockpit to all surfaces.
The nose enclosure, rudder controls, instrument panel, and front cockpit were destroyed by impact. The passenger compartment appeared largely intact. The front seatbelt, a single lap restraint, was released by rescue personnel. The rear seatbelt, a single lap belt, was secured at the buckle, but the right side seat belt mounting bracket was fractured. The bracket section attached at the belt was not recovered; the fracture surfaces on the bracket attached to the airframe exhibited overstress features. An FAA inspector confirmed that no shoulder harnesses were installed, and only a single lap belt restrained the two rear seat passengers.
Medical and Pathological Information
The Office of the Chief Medical Examiner, Burlington, Vermont, performed an autopsy on the pilot and determined cause of death as "blunt impacts." Toxicological testing by the FAA Forensic Sciences Laboratory was negative for drugs and alcohol.
Survival Aspects
The glider manufacturer specified that when properly equipped, the glider should have four shoulder harnesses: one for the pilot in the front seat, and three in the rear seat. With two passengers in the rear, each would use their respective outboard shoulder harness.
A survivability assessment by the FAA Office of Accident Investigation and Prevention and the Biodynamics Research Team examined the restraints. According to the biomedical research engineer, the Schweizer SGS 2-32 Type Certificate Data Sheet requires approved safety belts and shoulder harnesses for each occupant. In this accident, two rear seat occupants weighing 195 lbs and 185 lbs used a single lap belt. The combined weight on that single belt would have caused hardware failure at a much lower deceleration than designed, allowing occupant impact with structure. The weight should have been distributed among six hard points, but only two were used, contrary to the TCDS, significantly diminishing survivability.