Bell 47G-3B-1 accident near Panaca, Nevada, December 1, 2002
On December 1, 2002 at about 9:10 pm local time, a Bell 47G-3B-1 (helicopter), registered N48020, was substantially damaged in an accident near Panaca, Nevada. It was a public-use flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
separation of the no. 6 cylinder intake valve head from the valve stem, which resulted in a loss of engine power. The mechanism responsible for the valve failure is unknown.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 1, 2002 · about 9:10 pm local time
- Place
- Panaca, Nevada · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G-3B-1 · all 47G-3B-1s on the register
- Registration
- N48020 · registry record · serial 2812
- Damage
- Substantial damage
- Flight
- Public-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter experienced a loss of engine power and landed hard during an autorotation, severing the tail boom. The number 6 cylinder's intake valve separated, with the valve's head wedged in the intake valve seat bore. Removal of the rocker box cover on that cylinder revealed that the spring retainer was broken into numerous pieces. The piston head showed over 15 impressions consistent in dimension to that of the valve head. After examining the number 6 cylinder, a metallurgist determined that the valve failed in between the intake valve head and the valve stem.
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
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 29,351 hours in all; 16,120 in this make and model; 51 in the last 90 days; 17 in the last 30 days; 26,934 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 7,471 hours
- Last inspection: 100-hour inspection, October 31, 2002; 100 hours since
- Maximum gross weight: 2,950 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming TVO-435-B1A (piston); 0 hours total
The flight
- Departed from: Caliente NV at 8:00 pm
- Destination: Panaca NV
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 340° at 4 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 4,300 ft
- Temperature: 45°F (7°C), dew point 32°F (0°C)
- Altimeter: 30.12 inHg
- Observation at 9:53 pm from CDC, 63 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
Other NTSB records under N48020 the same tail number, which may have belonged to a different aircraft at the time
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.