Bell 47-G4A accident near Guam, August 26, 1996
On August 26, 1996 at about 11:15 am local time, a Bell 47-G4A (helicopter), registered N474GA, was destroyed in an accident near Guam. It was a business flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
loss of tail rotor control due to improper maintenance.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 26, 1996 · about 11:15 am local time
- Place
- Guam
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47-G4A · all 47-G4As on the register
- Registration
- N474GA · no longer on the register · serial 7580
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot was towing a banner offshore. Witnesses reported everything was normal until the banner fell free from the helicopter. At that point the helicopter started rotating to the right and descended into the bay. During the on-scene investigation, the retaining nut for the universal joint to yoke assembly on the tail rotor drive was found not engaged but retained the safety wire. The safety wire was broken on the last twist prior to entering the universal's affixing hole. The solid drive pin located in the aft universal and through the drive shaft was missing.
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: instructor: helicopter; rotorcraft: helicopter
- Flight time: 2,750 hours in all
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 2,378 hours
- Last inspection: annual inspection, May 17, 1996; 10 hours since
- Maximum gross weight: 2,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming VO-540 (piston); 0 hours total
- Operator: Hansen Helicopters INC.
The flight
- Departed from: NONE Tamuning OF at 10:30 am
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 290° at 6 knots
- Visibility: 7 statute miles
- Sky: scat at 2,000 ft
- Temperature: 88°F (31°C), dew point 75°F (24°C)
- Altimeter: 29.00 inHg
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
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.