Amateur-built THORPE T-18 accident near Stockton, California, July 3, 1994
On July 3, 1994 at about 2:58 pm local time, a amateur-built THORPE T-18, registered N51079, was substantially damaged in an accident near Stockton, California (Stockton Metro airport). It was a flight of an unrecorded kind 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
A VAPOR LOCK INDUCED ENGINE FAILURE DUE TO INADEQUATE THERMAL SHIELDING OF THE FUEL PUMP AND LINES. SOFT TERRAIN IN THE LANDING AREA WAS A FACTOR.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 3, 1994 · about 2:58 pm local time
- Place
- Stockton, California · Stockton Metro · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built THORPE T-18 THORPE T-1
- Registration
- N51079 · registry record · serial 988
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The accident flight was the second flight of the aircraft since certification on April 6, 1994. The aircraft has a Mazda NSU wankle rotary automobile engine installed and is operated on automotive gasoline. The pilot was on initial climbout after takeoff when the engine suddenly quit. The pilot was unable to make the runway and executed a forced landing in a field near the airport. The aircraft nosed over after encountering soft, rough terrain. The pilot reported that the fuel lines and fuel pump do not have any thermal shielding and he believes the engine failure was due to vapor lock.
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
- Ratings: single-engine land
- Flight time: 351 hours in all; 1 in this make and model; 3 in the last 90 days; 1 in the last 30 days; 351 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1 hours
- Last inspection: annual inspection, April 6, 1994; 1 hours since
- Maximum gross weight: 1,600 lb
- Seats: 2
- Landing gear: fixed
- Engine: Mazda NSU WANKLE (piston); 0 hours total
The flight
- Departed from: SCK at 2:58 pm
- Destination: SCK
- Flight plan: none
- Runway 29R, 8,600 ft by 150 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Visibility: 15 statute miles
- Sky: not recorded; clear
- Temperature: 72°F (22°C), dew point 0°F (-18°C)
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 N51079 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.