Bell 47G-3B-1 accident near Sedro Wooley, Washington, April 20, 1998
On April 20, 1998, a Bell 47G-3B-1 (helicopter), registered N80SD, was destroyed in an accident near Sedro Wooley, Washington. It was a personal flight under general aviation rules (Part 91). No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Fuel contamination and subsequent carburetor fuel flow restriction initiated by the use of an improper material (incorrect fuel hose). A factor was the trees.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 20, 1998
- Place
- Sedro Wooley, Washington · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G-3B-1 · all 47G-3B-1s on the register
- Registration
- N80SD · registry record · serial 3679
- Damage
- Destroyed
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During initial climb immediately after takeoff the helicopter lost power. The pilot attempted to maneuver to a clear area, but struck trees during the descent. Post crash examination revealed no mechanical malfunction with either the engine or carburetor although the carburetor had been subjected to a post crash fire and its fuel metering orifices could not be bench tested. Fuel samples taken from the helicopter's fuel tank prior to the accident, and from the fueling hose from the portable fuel truck were examined by a fuels testing lab and were found to contain 1,2-Benzenedicarboxylic acid, bis(2-ethylhexyl) ester. The pre-accident aircraft fuel sample, which contained a submersed glob of clear substance similar to that observed by the pilot seeping from the cut ends of the fueling hose, was tested. The test revealed that the 'soluble gum' consisted of 1,2-Benzenedicarboxylic acid, bis(2-ethylhexyl) ester' and that nearly 100% of the gum was soluble in the fuel. The operator was advised by the local distributor of the 'Versicon' hose that the hose was acceptable for use with aviation fuels. Specifications provided by the manufacturer of the hose, HBD Industries, provided a note which stated 'Not recommended for the variety of unleaded gas existing presently.'
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: private
- Ratings: rotorcraft: helicopter
- Flight time: 179 hours in all; 176 in this make and model
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: ctr
The aircraft
- Airframe total time: 32 hours
- Last inspection: 100-hour inspection, March 1, 1998; 5,198 hours since
- Maximum gross weight: 2,850 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming TVO-435-B1A (piston); 0 hours total
- Fire on the ground
The flight
- Destination: AWO Arlington WA
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 290° at 12 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 54°F (12°C), dew point 39°F (4°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.