NTSB Factual Report

On July 30, 2010 about 1450 eastern daylight time, a Schweizer 2-33A glider, N17965, was destroyed when it collided with trees and terrain following an in-flight fire and forced landing near Windsor, Virginia. The certificated private pilot suffered minor injuries. The glider was consumed in the subsequent post-crash fire. Visual meteorological conditions (VMC) prevailed, and no flight plan was filed for the local instructional flight which departed Garner Gliderport (3VA8), Windsor Virginia, about 1435 and was conducted under the provisions of 14 Code of Federal Regulations Part 91.

In both a telephone interview and a written statement the pilot said that he had stopped flying airplanes several years earlier, but recently began training to add a glider rating to his certificate. On the morning of the accident, the pilot arrived at the gliderport to practice for a "check ride" that was scheduled for 1600 that afternoon. The pilot selected and installed a "Gel-cell" battery behind the forward pilot seat during the preflight inspection of the glider. The battery was used to power the radio in the instrument panel.

The pilot completed a low-level, traffic pattern flight and was then towed to 3,000 feet msl for a second flight. The glider climbed to 3,400 feet about 5 miles from the gliderport where the pilot "smelled something." The pilot said the odor got stronger, he felt heat, looked behind him, and "saw fire in the back seat."

The pilot then "put out all spoilers" to complete an emergency descent. During the descent, the cockpit filled with smoke, and the pilot opened the canopy to clear the smoke. The smoke cleared, but the increased airflow "caused the fire to worsen."

The pilot completed a forced landing to trees short of the gliderport, and egressed the glider with only minor burns to the back of his head.

The pilot held a private pilot certificate with a rating for airplane single-engine land. He reported 180 total hours of flight experience; 140 hours of which were in single engine airplanes, and 40 hours of which were in gliders. The pilot did not hold a current Federal Aviation Administration (FAA) medical certificate, but neither was he required to for glider flights.

According to FAA and maintenance records, the glider was manufactured in 1973 and had accrued 1,545 total aircraft hours as of December 2, 2009, when the last annual inspection was completed. According an FAA safety inspector (airworthiness), examination of logbooks revealed the accident glider, and others in the soaring club fleet, had been modified to accommodate avionics and the batteries to power them. However, there were no logbook entries to reflect the work, or any FAA approval of the modifications.

At 1853, the weather conditions reported at Suffolk County Airport (SFQ), 12 miles south of the accident site, included clear skies, 10 miles visibility, and winds from 040 degrees at 9 knots. The temperature was 30 degrees Celsius (C), the dewpoint 19 degrees C, and the altimeter setting was 29.91 inches of mercury.

The glider was examined at the site on July 30, 2010, by FAA inspectors and all major components were accounted for at the scene. The glider rested upright in trees close to the ground, and the metal wings remained largely intact, though impact damaged. The fabric and wood-covered tubular metal frame was severely fire damaged. The battery and any recognizable electrical wiring was harvested and forwarded to the NTSB Materials Laboratory in Washington, DC, for examination at a later date.

On October 7, 2010, the battery and associated wiring from the accident glider were examined by a fire and explosion expert in the NTSB materials laboratory, Washington, D.C. The battery sustained too much fire-related damage to identify any signs of arcing on the contacts. The wiring had significant fire related damage and most of the insulation had burned away. The wiring showed no signs of arcing with the exception of one small bead on the end of a single conductor. The other conductors within that strand showed no signs of arcing or electrical damage. There were some signs of narrowing and necking on a few of the conductor ends. The rest of the conductor ends demonstrated either melting or fractures consistent with mechanical damage.

NTSB Probable Cause

The unauthorized installation of a battery and associated wiring and electrical components, which resulted in an in-flight electrical fire of undetermined origin.