Bell 206B-III accident near Hilo, Hawaii, November 21, 1992
On November 21, 1992 at about 9:15 pm local time, a Bell 206B-III (helicopter), registered N789N, was substantially damaged in an accident near Hilo, Hawaii. It was an other work-use flight under general aviation rules (Part 91). 3 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE PILOT'S INTENTIONAL FLIGHT IN AND NEAR A VOLCANIC GAS CLOUD WHICH INDUCED A PARTIAL LOSS OF ENGINE POWER DUE TO A LACK OF COMBUSTIBLE OXYGEN IN THE ATMOSPHERE.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 21, 1992 · about 9:15 pm local time
- Place
- Hilo, Hawaii · map
- Type
- Accident
- Injuries
- 3 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206B-III · all 206B-IIIs on the register
- Registration
- N789N · registry record · serial 1267
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE HELICOPTER WAS EQUIPPED WITH 2 CAMERAS AND WAS DOING FILMING RUNS OF A VOLCANO VENT CRATER AND ITS ASSOCIATED SMOKE PLUME FOR A MOTION PICTURE. THE PILOT SAID THAT ON THE THIRD PASS OVER THE CRATER HE NOTICED THE MAIN ROTOR RPM DECREASING AND SAW THE ROTOR CAUTION LIGHT. HE SAID HE LOWERED THE COLLECTIVE AND INADVERTENTLY ENTERED THE VOLCANO SMOKE AND STEAM CLOUD. AFTER TURNING HE EXITED THE CLOUD AND AUTOROTATED TO THE CRATER BOTTOM. THE MAIN ROTOR STRUCK THE SHEAR ROCK WALL DURING THE FLARE AND SEPARATED FROM THE HELICOPTER. TWO CAMERA OPERATORS ONBOARD SAID THE PILOT ANNOUNCED 'WE'VE GOT A PROBLEM' AS THEY ENTERED THE SMOKE CLOUD. BOTH WITNESSES SAID THEY DID NOT HEAR THE LOW ROTOR WARNING TONE AND PERCEIVED NO CHANGE IN ENGINE SOUND DURING THE EVENT. ONE SAID HE FELT 'SIDEWARD YAWING MOTIONS' DURING THE DESCENT. THE CAMERA OPERATORS SAID THAT AFTER THE HELICOPTER EMERGED FROM THE CLOUD NEAR THE BOTTOM OF THE CRATER THE ROTOR STRUCK THE ROCK WALL.
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: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; rotorcraft: helicopter
- Flight time: 8,762 hours in all; 2,239 in this make and model; 91 in the last 90 days; 26 in the last 30 days; 8,509 as pilot in command; 858 on instruments
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 13,609 hours
- Last inspection: 100-hour inspection, December 16, 1992; 10 hours since
- Maximum gross weight: 3,200 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Departed from: NONE Hilo HI at 8:45 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 090° at 5 knots
- Visibility: 5 statute miles
- Sky: broken clouds at 2,000 ft; clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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.
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.