History of Flight
On April 24, 2009, at an undetermined time, an experimental Valentin Taifun 17 E II motor-glider, registration N20822, collided with terrain under unknown circumstances near Mammoth Lakes, California. The pilot/owner was operating the aircraft under 14 Code of Federal Regulations Part 91. The certificated private pilot and one passenger were killed; the airplane sustained substantial damage to the wings, fuselage, and empennage from impact forces. The cross-country personal flight departed Tonopah, Nevada, around 1500 Pacific daylight time, with a planned destination of Modesto, California. Visual meteorological conditions prevailed at Mammoth Lakes, the nearest reporting station, and no flight plan was filed. The Federal Aviation Administration (FAA) issued an alert notice after family members reported the airplane overdue. The Civil Air Patrol discovered the wreckage on May 1, 2009.
Personnel Information
The 67-year-old pilot held a private pilot certificate with ratings for airplane single-engine land, instrument airplane, and glider. His third-class medical certificate, issued on May 27, 2008, required corrective lenses. According to excerpts from the pilot's logbook, his estimated total flight time was 966 hours as of the last entry on April 16, 2009. He logged 19 hours in the previous 90 days and 8 hours in the last 30 days, with approximately 310 hours in gliders. He completed a biennial flight review on May 28, 2008.
Aircraft Information
The airplane was an experimental Valentin Taifun 17 E II, serial number 1116. The airframe had a total time of 235 hours at the last 100-hour inspection on March 26, 2008, and an annual inspection entry dated January 29, 2008. The engine was a Limbach L2400, serial number 1078. Flight log excerpts indicated that on July 31, 2008, at a total engine time of 243.5 hours, the time since major overhaul was 8 hours. The last flight log entry showed a total time of 313.5 hours on April 20, 2009.
Meteorological Information
Mammoth Lakes Airport (KMMH) was 10 nautical miles at 140 degrees from the accident site, at an elevation of 7,135 feet mean sea level. A METAR at 1510 PDT reported calm winds, visibility 10 miles, overcast ceiling at 4,200 feet, temperature 7°C, dew point -4°C, and altimeter 29.89 inHg. A METAR at 1610 PDT indicated wind 230° at 10 knots gusting to 24 knots, visibility 10 miles, scattered clouds at 2,900 feet and overcast at 4,100 feet, temperature 7°C, dew point -5°C, altimeter 29.87 inHg. A METAR at 1710 PDT reported wind 290° at 15 knots gusting to 22 knots, visibility 10 miles, broken clouds at 3,300, 4,000, and 4,800 feet, temperature 3°C, dew point -3°C, altimeter 29.89 inHg. A weather station at June Lake, California (elevation 7,960 feet), 7 nm from the accident site, recorded winds from the north at 6 knots gusting to 14 knots at 1502, and later winds from the southeast at 4 knots gusting to 10 knots at 1611, and 6 knots gusting to 12 knots at 1711. A station at Crestview, California (elevation 7,596 feet), 4 nm away, reported winds from the northeast at 5 knots gusting to 18 knots at 1512, and from the northeast at 5 knots gusting to 17 knots at 1623 and 1713.
Wreckage and Impact Information
An FAA inspector examined the wreckage. The fuselage came to rest in a small open area with the nose oriented approximately 090°, at GPS coordinates 37°46.769'N, 118°57.366'W, elevation about 8,000 feet msl. The debris path extended along 315° into a shallow canyon. The first impact with tree tops occurred about 325 feet from the final resting position. As the airplane passed through 50–75 foot pine trees, both wings separated. The right wing lay about 35 feet from the fuselage, its aileron and flap about 25 feet away, and the wing tip was in a tree. The left wing was about 30 feet from the fuselage; its aileron and flap were nearby. Both wings sustained leading-edge damage from tree strikes. One propeller blade tip was found near the left wing; the other was located about 120 feet beyond the fuselage. Both wood propeller blades were fragmented. Rudder continuity was verified. Fore/aft control stick movement was limited and required moderate force; the control rod was broken aft of the cockpit at a threaded fitting, but the aft portion was intact and elevator movement could be verified. The area aft of the cockpit was crushed, and the aileron mixer assembly was damaged. Left/right stick movement was limited but the mixer assembly could be actuated to the right wing attach point. The spoiler actuation system could not be positively identified in the fuselage; both spoilers were intact and retracted in the wings and could be actuated at the wing roots. Both left and right ailerons and flaps had separated from their wings, with control rods intact and attached to bell cranks. The ignition key was in the on position; the master switch was on; all other switches were off except the beacon switch. The throttle was full in, along with the fuel valve and choke.
Medical and Pathological Information
The Mono County Coroner performed an autopsy and determined the cause of death as multiple traumatic injuries. The FAA Forensic Toxicology Research Team analyzed pilot specimens and found no carbon monoxide, cyanide, volatiles, or tested drugs.
Tests and Research
Examination of the engine revealed no anomalies that would have precluded normal operation.