Amateur-built THORP T-18 accident near Claremont, California, September 25, 1990
On September 25, 1990, a amateur-built THORP T-18, registered N9JE, was substantially damaged in an accident near Claremont, California. It was a personal flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A LOSS OF CONTROL FOR UNDETERMINED REASON(S).
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 25, 1990
- Place
- Claremont, California · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built THORP T-18
- Registration
- N9JE · no longer on the register · serial 892
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
GROUND WITNESSES OBSERVED THE AIRCRAFT IN A SPIN, AND THEN COLLIDE WITH THE TERRAIN. THEY DID NOT HEAR THE ENGINE OR UNUSUAL NOISES. EXAMINATION OF THE AIRCRAFT STRUCTURE, FLIGHT CONTROLS, AND ENGINE REVEALED NO EVIDENCE OF A PREIMPACT MECHANICAL DIFFICULTY.
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: 362 hours in all; 320 in this make and model; 313 as pilot in command
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 221 hours
- Last inspection: annual inspection, January 1, 1990; 11 hours since
- Maximum gross weight: 1,525 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-E2D (piston); 0 hours total
The flight
- Departed from: POC La Verne CA at 11:06 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 240° at 7 knots
- Visibility: 7 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Altimeter: 29.00 inHg
- Observation at 11:46 pm from POC, 5 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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 N9JE 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.