American AA-1 accident near San Martin, California, October 22, 2003
On October 22, 2003 at about 10:15 pm local time, a American AA-1, registered N5968L, was substantially damaged in an accident near San Martin, California (South County Airport). It was a personal flight under general aviation rules (Part 91). 2 people were seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The absence of compression in two of the airplane's four cylinders, and the pilot/mechanic's failure to maintain the engine in an airworthy condition, which resulted in a loss of engine power during takeoff-initial climb, and subsequent forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 22, 2003 · about 10:15 pm local time
- Place
- San Martin, California · South County Airport · map
- Type
- Accident
- Injuries
- 2 people were seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- American AA-1 · all AA-1s on the register
- Registration
- N5968L · no longer on the register · serial 268
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The student pilot/airplane owner, who is also an aviation mechanic, reported a loss of engine power after takeoff during the initial climb. He said the engine was running rough, and started to lose power. He was unable to maintain altitude, and made a forced landing. The airplane collided with a fence during the landing roll. An examination of the engine disclosed virtually no compression in two of the four cylinders, an absence of an air cleaner, excessively wide gaps on all of bottom spark plugs, and a heavily sooted and fouled number 4 top spark plug. The engine was installed in July, 1978, and had accumulated 2157.5 total operating hours; it has never been overhauled.
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
Dual student
- Certificate: student
- Flight time: 121 hours in all; 112 in this make and model; 7 in the last 90 days; 2 in the last 30 days
- Last flight review: September 15, 2003
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: serious injuries
The aircraft
- Airframe total time: 3,343.4 hours
- Last inspection: 100-hour inspection, March 1, 2003
- Maximum gross weight: 1,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-235-C2C (piston); 0 hours total
The flight
- Departed from: KQ99 San Martin CA at 10:15 pm
- Destination: KWLW Willows CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 300° at 14 knots
- Visibility: 15 statute miles
- Sky: broken clouds at 20,000 ft; clear
- Temperature: 72°F (22°C), dew point 55°F (13°C)
- Altimeter: 30.10 inHg
- Observation at 10:24 pm from KRHV, 28 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.
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.