History of Flight
On August 7, 2020, about 1230 Pacific daylight time, a Sportine Aviacija Lak-17B FES Mini motorized glider, N290MH, was substantially damaged during an accident near Lakeport, California. The private pilot was fatally injured. The glider was operated as a personal flight under Title 14 Code of Federal Regulations Part 91.
The pilot departed from runway 28 at Lampson Field Airport (1O2) about 1200 for a local flight. A video recorded from the start end of runway 28 showed a family member acting as a wing runner during the takeoff roll. The glider began on the left side of the runway and became airborne after about 1,000 ft of ground roll. It maintained runway heading in a steep climb to about 500 ft above ground level before moving out of view. The motor was audible throughout the video.
When the pilot did not return, family members checked his personal locator beacon, which indicated his last position. The accident site was located later that day. No witnesses to the accident were identified.
Flight track data from an onboard flight computer showed the pilot performed turning maneuvers within 2 miles of the airport for about 20 minutes. The glider reached a maximum altitude of 2,871 ft mean sea level (about 1,500 ft agl), then slowly descended. Near the accident site, the data indicated a short, steep climb followed by a left turn and descent of about 70 ft; the last recorded altitude was about 564 ft agl.
Personnel Information
The pilot purchased the glider several months before the accident. He had logged over 1,500 hours of flight experience in gliders but less than 5 hours in the accident glider. The pilot had recently imported the glider and was fulfilling FAA airworthiness requirements, coordinating with a designated airworthiness representative (DAR) to complete three takeoffs and landings and five hours of flight time. In an email dated July 9, 2020, the pilot requested to change the location of introductory flights from Lampson Field to Air Sailing Gliderport (NV23) in Sparks, Nevada, where he had flown for the past 18 years. He stated he would become more acquainted with the glider by taking several aerotows before self launches. The request was approved the next day. On July 12, 2020, the pilot conducted an aerotow at NV23 and completed a 4-hour 15-minute flight in the accident glider.
Aircraft Information
The single-seat, high-performance motor glider, serial number 029, was manufactured in 2020. According to the airframe logbook, the glider had less than 5 total hours of flight time before the accident flight. It was equipped with a single-shaft, 23-kilowatt FES-LAK-M100 front electric sustainer (FES) motor powering a two-bladed, 1-meter diameter foldable propeller. The propeller blades folded aft against the fuselage when not in use. The motor was powered by two 116-volt batteries behind the cabin.
Per the glider flight manual, normal operating airspeed was 54 to 92 kts, with a never-exceed speed of 124 kts in smooth air. The glider was equipped with an LXNav LX9000 glide computer/GPS that captured flight information.
According to a family member and flight track data, on June 20, 2020, before the pilot’s first orientation flight, the spoiler sensor and landing gear sensor were installed in the wrong positions. The propeller blades would not retract after a FES ground run. The sensors were repaired. During that flight, the FES overheated and was shut down before reaching planned altitude. While returning to the airport, the FES restarted and was shut down again. The propeller continued to rotate during descent and blades would not retract. During landing, the pilot kept the nose up to prevent propeller blade impact with the runway, resulting in a blown main tire. The landing gear was repaired, and electronic downloads were installed to adjust the propeller docking position. An adjustment was also made to avoid radio activation of the FES. The electronic downloads were not found in the logbooks.
Wreckage and Impact Information
The wreckage was located on steep, wooded terrain about 1 mile west of the departure end of runway 28. According to first responders’ photos, the glider was found in multiple sections scattered within about a 100 ft radius. Trees and bushes near the debris field were not damaged.
Due to the Covid-19 pandemic, the NTSB did not travel to the accident site. Local law enforcement responded and photographic documentation was obtained. An airframe examination was performed at the site, and the wreckage was recovered for further examination.
Postaccident examination revealed the forward fuselage had excessive impact damage and was found in multiple sections. The motor remained attached to the forward support structure and instrument panel, which separated from the main wreckage. Battery cables and wires near the motor were cut during recovery. The propeller blades separated from the motor hub and exhibited impact damage and rotational scuff marks. Both blades’ mounting ends remained attached to the hub. The spinner had rotational scoring near the aft edge and impact damage near the blade mounts, consistent with the blades being in the deployed (forward) position. The motor housing showed rotational scoring. The motor rotated normally by hand; the air vent linkage operated normally. No evidence of preexisting malfunctions or failures that would have precluded normal operation was found.
Medical and Pathological Information
An autopsy by Bennett Omalu Pathology determined the cause of death as high velocity polytrauma. Severe atherosclerotic heart disease was identified, with up to 90% stenosis of the left anterior descending and right coronary arteries, but no scarring from previous ischemia was found.
Toxicology testing by Central Valley Toxicology Inc. detected ethanol in chest blood at 0.14 gm/dl; no other common acidic, neutral, or basic drugs were identified. The FAA’s Forensic Sciences Laboratory found ethanol at 0.130 gm/dl and N-propanol in cavity blood, but no ethanol in vitreous fluid. No other tested-for substances were detected.