Bell 47G-5 accident near Porterville, California, July 8, 1986
On July 8, 1986 at about 4:15 pm local time, a Bell 47G-5 (helicopter), registered N1316X, was substantially damaged in an accident near Porterville, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person was seriously injured; 2 others were unhurt. 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
- July 8, 1986 · about 4:15 pm local time
- Place
- Porterville, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured; 2 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G-5 · all 47G-5s on the register
- Registration
- N1316X · no longer on the register · serial 7827
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
DURING AN AERIAL APPLICATION FLIGHT THE PLT LOST CONTROL OF THE HELICOPTER AND COLLIDED WITH A BUILDING. EXAMINATION REVEALED THAT THE INSIDE DIAMETER OF THE TAIL ROTOR DRIVESHAFT WAS NOT COATED WITH ALUMINIZED LACQUER AS REQUIRED BY THE BELL FINISH PROCESS SPECIFICATION. THE BELL DRAWING REQUIRES TWO #2 SHORT PLUGS TO BE INSTALLED AT A SPECIFIED DISTANCE FROM EACH END OF THE TAIL ROTOR DRIVESHAFT AND THE END OF THE SHAFT TO BE SEALED OFF WITH ADHESIVE TO PROTECT THE SHAFT INSIDE DIAMETER FROM CORROSION. A DIMENSIONAL CHECK OF THE SHAFT REVEALED THAT THE PLUGS WERE NOT INSTALLED AT THE CORRECT DISTANCE FROM THE END OF THE SHAFT AS SPECIFIED IN THE DRAWING.
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: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Flight time: 10,077 hours in all; 5,000 in this make and model; 110 in the last 90 days; 9,801 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 5,951 hours
- Last inspection: annual inspection, July 1, 1985; 289 hours since
- Maximum gross weight: 2,850 lb
- Seats: 3
- Landing gear: fixed
- Engine: Lycoming VO-435-B1A (piston); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 | ||
| Passengers | 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.
Other NTSB records under N1316X the same tail number, which may have belonged to a different aircraft at the time
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.