Bell 206B accident near Fairbanks, Alaska, August 25, 1992
On August 25, 1992 at about 5:43 pm local time, a Bell 206B (helicopter), registered N83139, was substantially damaged in an accident near Fairbanks, Alaska (Fairbanks airport). It was a public-use flight under public-use (government) rules. No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
POOR MAINTENANCE AND INSPECTION PROCEDURES BY THE CONTRACT MAINTENANCE PERSONNEL, AS WELL AS IMPROPER MAINTENANCE AND INSTALLATION OF THE FUEL LINE BY THE CONTRACT MAINTENANCE PERSONNEL. FACTORS RELATING TO THE ACCIDENT WERE THE TURBOSHAFT ENGINE VIBRATIONS AND THE CRACKED FUEL LINE(S).
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 25, 1992 · about 5:43 pm local time
- Place
- Fairbanks, Alaska · Fairbanks · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206B · all 206Bs on the register
- Registration
- N83139 · no longer on the register · serial 1018
- Damage
- Substantial damage
- Flight
- Public-use flight · public-use (government) rules
The NTSB's narrative final · quoted from the NTSB record
THE STATE OF ALASKA HELICOPTER EXPERIENCED A FUEL LEAK AND AN UNEVENTFUL PRECAUTIONARY LANDING. THE LEAKING FUEL LINE WAS REPLACED IN FIELD MAINTENANCE WITHOUT MANUFACTURER'S REQUIRED SECURING CLAMPS. A SECOND FUEL LEAK, PRECAUTIONARY LANDING AND FUEL LINE REPLACEMENT WAS EFFECTED, AGAIN WITHOUT CLAMPS. A THIRD FUEL LEAK AT THE SAME REPLACEMENT LINE WAS FOLLOWED BY A FIRE FOLLOWING A PRECUATIONARY LANDING. THE NTSB SUPERVISED MANUFACTURER'S ENGINE EXAMINATION REVEALED VIBRATION IN ROTATING COMPONENTS OF 15 TIMES THE ALLOWED LIMITS, AS WELL AS A FATIGUE CRACK IN THE HOT SECTION. THESE VIBRATIONS AND CRACKS WERE NOT DISCOVERED DURING ENGINE MAINTENANCE AND INSPECTIONS BY COMPANY CONTRACT MAINTENANCE PERSONNEL. THE METALLURGICAL EXAMINATION OF THE FUEL LINES IN EACH EVENT REVEALED FATIGUE PROPAGATION AND THE LACK OF CLAMP MARKS ON THE FUEL LINES FROM EVENTS 2 AND 3.
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: airline transport pilot
- Ratings: single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 8,700 hours in all; 4,500 in this make and model; 100 in the last 90 days; 40 in the last 30 days; 8,000 as pilot in command; 1,200 on instruments
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 11,658 hours
- Last inspection: 100-hour inspection, June 30, 1992; 39 hours since
- Maximum gross weight: 3,200 lb
- Seats: 5
- Landing gear: fixed
- Engine: Allison 250-C20 (turboshaft); 0 hours total
- Fire in flight and on the ground
The flight
- Departed from: FAI at 12:32 pm
- Destination: TKJ Tok AK
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 360° at 8 knots
- Sky: scat at 25,000 ft
- Temperature: 52°F (11°C), dew point 39°F (4°C)
- Altimeter: 29.00 inHg
- Observation at 12:43 pm from FAI, 1 miles away
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.
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.