Bell 47G3-B1 accident near Moultonboro, New Hampshire, October 7, 1984
On October 7, 1984 at about 9:55 pm local time, a Bell 47G3-B1 (helicopter), registered N401GC, was substantially damaged in an accident near Moultonboro, New Hampshire (Moultonboro airport). It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). 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
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 7, 1984 · about 9:55 pm local time
- Place
- Moultonboro, New Hampshire · Moultonboro
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G3-B1 · all 47G3-B1s on the register
- Registration
- N401GC · no longer on the register · serial 3568
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
ACFT WAS CLIMBING THROUGH A MOUNTAIN SADDLE WHEN THE ENGINE BEGAN TO BACKFIRE AND LOSE POWER. PLT ENTERED AUTOROTATION & SETTLED INTO TREES ON AUTOROTATIVE FLARE. ENGINE INSPECTION REVEALED #3 CYLINDER INTAKE VALVE SPRINGS BROKEN.
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: instrument: helicopter; rotorcraft: helicopter
- Flight time: 2,229 hours in all; 295 in this make and model; 245 in the last 90 days; 1,996 as pilot in command
- Medical certificate: None (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 5,822 hours
- Last inspection: 100-hour inspection, February 27, 1984; 89 hours since
- Maximum gross weight: 2,950 lb
- Seats: 3
- Landing gear: retractable
- Engine: Lycoming VO-435-A1F (piston); 0 hours total
The flight
- Departed from: HN08 Moultonboro VT at 7:52 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 12 statute miles
- Sky: clear
- Temperature: 52°F (11°C), dew point 0°F (-18°C)
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.