Valentin TAIFUN 17 E II accident near Mammoth Lakes, California, April 24, 2009
On April 24, 2009, a Valentin TAIFUN 17 E II, registered N20822, was substantially damaged in an accident near Mammoth Lakes, California. It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to maintain clearance from terrain while maneuvering in a canyon.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 24, 2009
- Place
- Mammoth Lakes, California · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Valentin TAIFUN 17 E II
- Registration
- N20822 · registry record · serial 1116
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The motor-glider wreckage was located in mountainous terrain at an elevation of about 8,000-feet. The wreckage debris path was dispersed throughout trees and extended for 325 feet in a shallow canyon. The nearest weather reporting station, located about 10 miles from the accident site, indicated that around the time of departure, there was a cloud ceiling at 4,200 feet with calm wind. The ceiling observation was lowered to 3,300 feet about 2 hours later, with the wind gusting from 10 to 24 knots. Postaccident inspection of the airframe and engine revealed no anomalies that would have precluded normal operation. The circumstances leading up to the accident could not be determined.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Collision with terrain or object (not controlled flight into terrain) during unknown defining event
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Environmental issues › Physical environment › Object/animal/substance › Tree(s) › Contributed to outcome
- Environmental issues › Physical environment › Terrain › Mountainous/hilly terrain › Contributed to outcome
- Environmental issues › Conditions/weather/phenomena › Ceiling/visibility/precip › Low ceiling › Not specified
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Altitude › Not attained/maintained
Pilot
- Certificate: private
- Ratings: single-engine land; instrument: airplane; rotorcraft: glider
- Flight time: 966 hours in all; 64 in this make and model; 19 in the last 90 days; 8 in the last 30 days; 911 as pilot in command
- Last flight review: May 28, 2008
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 235 hours
- Last inspection: 100-hour inspection, March 26, 2008
- Seats: 2
- Landing gear: retractable
- Engine: Limbach L2400 (piston); 0 hours total
The flight
- Departed from: TPH Tonopah NV at 10:00 pm
- Destination: MOD Modesto CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: at 10 knots, gusting 24
- Visibility: 10 statute miles
- Sky: overcast at 4,100 ft; scat at 2,900 ft
- Temperature: 45°F (7°C), dew point 23°F (-5°C)
- Altimeter: 29.87 inHg
- Observation at 11:10 pm from KMMH, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.