Bell TH-1L accident near Etna, California, February 23, 1994
On February 23, 1994 at about 7:00 pm local time, a Bell TH-1L (helicopter), registered N204AP, was substantially damaged in an accident near Etna, California. It was a flight of an unrecorded kind under external-load helicopter rules (Part 133). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE FAITUGE OF THE GEAR TOOTH WHICH CAUSED THE FAILURE OF THE 42-DEGREE GEAR BOX.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 23, 1994 · about 7:00 pm local time
- Place
- Etna, California · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell TH-1L
- Registration
- N204AP · no longer on the register · serial 157840
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
THE 42-DEGREE GEAR BOX FAILED SHORTLY AFTER DEPARTING ON A HELICOPTER LOGGING OPERATION. THE PILOT JETTISONED THE LOAD, BUT WAS UNABLE TO STOP THE HELICOPTER'S ROTATION AND IT CRASHED. METALLURGICAL EXAMINATION OF THE GEAR BOX REVEALED A FATIGUE BANDING PATTERN NEAR THE TOOTH ROOT OF THE INPUT GEAR.
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: single-engine land; rotorcraft: helicopter
- Flight time: 14,018 hours in all; 3,400 in this make and model; 225 in the last 90 days; 165 in the last 30 days; 13,325 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Last inspection: continuous airworthiness programme
- Maximum gross weight: 9,500 lb
- Seats: 7
- Landing gear: fixed
- Engine: Lycoming T53-L13 (turboshaft); 0 hours total
- Operator: Hiser Helicopters INC.
The flight
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: at 5 knots, gusting 7
- Visibility: 40 statute miles
- Sky: scat at 4,000 ft
- Temperature: 34°F (1°C), dew point 27°F (-3°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
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 N204AP 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.