Bell UH-1B accident near Chowchilla, California, April 16, 1986
On April 16, 1986 at about 7:24 pm local time, a Bell UH-1B (helicopter), registered N910PD, was destroyed in an accident near Chowchilla, California. It was a ferry flight under general aviation rules (Part 91). 1 person had minor injuries. 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
- April 16, 1986 · about 7:24 pm local time
- Place
- Chowchilla, California · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell UH-1B · all UH-1Bs on the register
- Registration
- N910PD · no longer on the register · serial 474
- Damage
- Destroyed
- Flight
- Ferry flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
WHILE RETURNING FROM A SPRAYING OPERATION THE PLT OBSERVED THAT THE MAIN TRANSMISSION OIL PRESSURE GAGE INDICATED ZERO. THE PLT REPORTED THAT THE ENGINE MASTER CAUTION DID NOT ILLUMINATE AND THAT THE OIL TEMPERATURE GAGE WAS NORMAL. THE PLT STATED THAT HE DECIDED THAT THE OIL PRESSURE GAGE WAS FAULTY AND ELECTED TO CONTINUE THE FLT. ABOUT 5 MINUTES LATER, THE TRANSMISSION OIL TEMP GAGE BEGAN TO RISE RAPIDLY.THE HELICOPTER BEGAN TO SHAKE VIOLENTLY AND THE MAIN ROTOR RPM BEGAN TO DECAY. THE PLT, UNABLE TO PERFORM AN AUTOROTATION DUE TO LOW ROTOR RPM EXECUTED A POWER ON LANDING, AND THE HELICOPTER ROLLED OVER AT IMPACT. POST ACCIDENT INVESTIGATION DISCLOSED THE OIL COLLER HOUSING GASKET WAS DAMAGED AND THE TRANSMISSION OIL RESERVOIR DID NOT CONTAIN ANY OIL. THE TRANSMISSION OUTER HOUSING AND PLANETARY GEARS EXHIBITED HIGH TEMPERATURE DISTRESS.
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: single-engine land; instructor: helicopter; instrument: airplane; rotorcraft: helicopter
- Flight time: 10,000 hours in all; 50 in the last 90 days; 20 in the last 30 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 9,090 hours
- Last inspection: annual inspection, July 1, 1985; 65 hours since
- Maximum gross weight: 8,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming T53-L11D (turboshaft); 0 hours total
- Operator: San Joaquin Helicopter, INC.
The flight
- Departed from: Snelling CA at 7:15 pm
- Destination: DLO Delano CA
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 15 statute miles
- Sky: scat at 3,000 ft
- Temperature: 63°F (17°C), dew point 37°F (3°C)
- Altimeter: 30.00 inHg
- Observation at 3:50 am from FAT, 20 miles away
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.
Other NTSB records under N910PD 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.