Amateur-built AA-5B accident near Oakdale, California, October 8, 2006
On October 8, 2006 at about 8:16 pm local time, a amateur-built AA-5B, registered N39ER, was substantially damaged in an accident near Oakdale, California (Kistler airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A total loss of engine power resulting from lubrication deprivation for undetermined reasons.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 8, 2006 · about 8:16 pm local time
- Place
- Oakdale, California · Kistler · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built AA-5B
- Registration
- N39ER · no longer on the register · serial AA5B0901
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
Upon experiencing a total loss of engine power during cruise flight, the pilot made a forced landing during which the airplane overran the runway's departure end and impacted a fence. The pilot reported that during the flight she "heard an abnormal noise coming from the engine - a loud knocking sound. Within just a few seconds, the engine exploded and a rush of oil from the engine compartment flooded the wind screen, obscuring about 90 percent of the forward field of view....The cabin started to fill with smoke from burnt oil," and the propeller stopped rotating. The pilot force landed on a 2,000-foot-long airstrip. Upon exiting the airplane the pilot observed that the top portion of the engine's case was punctured. The pilot had purchased the 1978 model airplane earlier during 2006, and she had possession of its maintenance records. The records indicated that the engine received three (field) overhauls in 1980, 1991, and in 1994. By the accident date, the engine's total time and time since last overhaul was 5,538 and 950 hours, respectively. Examination of the engine found that it had sustained an internal catastrophic mechanical failure, which resulted in a breach of the crankcase at the forward top section. The oil lines were found secure at their respective engine fittings, the crankshaft and respective connecting rods exhibited severe heat distress consistent with lubrication deprivation. The number 1, 2 and 4 connecting rods were displaced from their respective journals. The number 3 connecting rod remained on the journal, which exhibited severe heat distress. The crankshaft and camshaft remained intact. No anomalies were found with the accessory components and gears, or with the lubricating system. The specific event leading to the lubrication deprivation and heat distress was not identified.
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: 246 hours in all; 51 in this make and model; 15 in the last 90 days; 1 in the last 30 days; 90 as pilot in command
- Last flight review: November 1, 2005
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Maximum gross weight: 2,400 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-360-A4K (piston); 0 hours total
The flight
- Departed from: E45 Groveland CA at 7:45 pm
- Destination: SQL San Carlos CA
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 45°F (7°C)
- Altimeter: 30.00 inHg
- Observation at 7:53 pm from MOD, 24 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.