Piper PA-28-140 accident near Plymouth, California, October 3, 1996
On October 3, 1996 at about 7:15 pm local time, a Piper PA-28-140, registered N5705U, was substantially damaged in an accident near Plymouth, California. 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
failure of the #3 exhaust valve, which resulted in loss of engine power, a forced landing, and subsequent collision with a fence post.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 3, 1996 · about 7:15 pm local time
- Place
- Plymouth, California · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-28-140 · all PA-28-140s on the register
- Registration
- N5705U · no longer on the register · serial 28-26502
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During flight, the pilot noted a severe engine vibration. He also noted a drop in engine rpm, EGT, and engine oil pressure, along with a loss of power. The engine rpm and oil pressure continued to drop, and the pilot was unable to maintain altitude. Also, the pilot noted smoke in the cockpit, which prompted him to make a forced landing. During the landing, the right wing struck a fence post. An inspection revealed that the #3 cylinder had ingested portions of the #3 exhaust valve. The exhaust valve fracture surfaces were peened.
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: single-engine land
- Flight time: 136 hours in all; 29 in the last 90 days; 9 in the last 30 days; 56 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 4,369 hours
- Last inspection: annual inspection, April 14, 1996; 40 hours since
- Maximum gross weight: 2,150 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-E2A (piston); 0 hours total
The flight
- Departed from: O70 Jackson CA at 6:40 pm
- Destination: AUN Auburn CA
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: at 4 knots
- Visibility: 7 statute miles
- Sky: scat at 25,000 ft
- Temperature: 25°F (-4°C), dew point 12°F (-11°C)
- Altimeter: 30.00 inHg
- Observation at 7:47 pm from SAC, 56 miles away
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.