History of Flight
On June 29, 2009, at 1415 Pacific Daylight Time, an Alexander Schleicher GMBH and Company ASW 27-18E glider, registered as N129TD, broke apart in midair while maneuvering in thermal activity approximately 10 miles north of Ephrata, Washington. The private pilot was operating the glider under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed. The glider had departed from Ephrata Municipal Airport.
According to a witness who was also participating in a glider competition, the accident glider was seen circling in a thermal. The witness observed the glider stall and enter a spin. After three turns in the spin, the glider transitioned to a high-speed spiral dive. During the spiral, the wing separated due to heavy G-loads, and the glider then dove into the ground at high speed.
Another witness reported seeing the glider ahead while maneuvering in a thermal. He noted the glider's competition number, X8, and estimated they were about 500 feet apart. He observed the glider yaw to the right and enter a right-hand spin. After three complete turns, the wing recovered from the stall but the rotation continued, quickly transitioning into a tight spiral. The witness saw the wingtips arch upward from severe positive G-loading, and then the wings disintegrated.
Pilot Information
The pilot, age 52, held a private pilot certificate for single- and multi-engine airplanes, single-engine seaplanes, and gliders, as well as an instrument rating. His last third-class medical certificate was issued on May 2, 2008, with a restriction that he must have glasses available for near vision. On his last medical application, the pilot reported 3,200 total flight hours, with 80 hours in the previous six months. Excerpts from his logbooks showed 456 total glider hours as of August 2008. He obtained a single-engine seaplane rating on April 17, 2009, which served as his flight review.
Glider Information
The glider, serial number 29567, received its airworthiness certificate in November 2008. It was equipped with a Solo Type 2350 engine and a Schleicher AS2F1-2/L120-43-N2 propeller. According to Federal Aviation Administration records, the glider was registered to its current owner on November 4, 2008.
Meteorological Information
At 1453, an aviation routine weather report from Ephrata Municipal Airport reported winds from 220 degrees at 7 knots, visibility 10 statute miles, clear sky, temperature 81 degrees Fahrenheit, dew point 30 degrees Fahrenheit, and altimeter 29.92 inches of mercury.
Flight Recorders
A Colibri flight recorder was recovered from the wreckage. The data-storing SD card was cracked, and the manufacturer indicated that no data retrieval was possible.
Wreckage and Impact Information
The main wreckage came to rest in a wheat field at an elevation of approximately 2,600 feet mean sea level. Multiple pieces of the glider had separated and were not located in the immediate vicinity. The debris path was oriented on a 130-degree heading. Recovered pieces included the impact crater, engine, tailboom, wing sections, and other composite fragments.
Medical and Pathological Information
The Douglas County Coroner completed an autopsy, classifying the manner of death as accident from injuries sustained in the accident. The FAA Bioaeronautical Research Laboratory performed toxicology testing, which detected nordiazepam and tetrahydrocannabinol (marihuana) in various tissues. Ethanol was detected in muscle but was determined to be from sources other than ingestion.
Tests and Research
Examination of the wreckage revealed extensive fragmentation. All flight control surfaces or portions were identified. The vertical stabilizer was split, rudder cables were continuous. The right outboard horizontal stabilizer had a puncture hole. The left inner wing separated at the center fork and midspan. The right wing was extensively fragmented. Center section fork pins remained in place but spars had separated.