Piper PA-28-181 accident near Lopez Island, Washington, August 25, 2007
On August 25, 2007, a Piper PA-28-181, registered N2939J, was substantially damaged in an accident near Lopez Island, Washington (Lopez Island 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 loss of engine power due to the fatigue failure of the left idler gear. Inadequate maintenance installation of the recently installed left magneto was also causal.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 25, 2007
- Place
- Lopez Island, Washington · Lopez Island Airport
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-28-181 · all PA-28-181s on the register
- Registration
- N2939J · registry record · serial 28-7990576
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While en route to the destination airport, the pilot heard the engine generate a loud "bang," as though something had shattered internally. The engine subsequently experienced a total loss of power. The pilot maneuvered the airplane to a pasture where the airplane collided with a fence during the landing roll. According to the engine logbooks, the last engine annual inspection had been performed about 6 months and 124 hours prior to the accident. The left magneto had been replaced about 3 months and 54 hours prior to the accident. A teardown inspection of the engine disclosed that the left idler gear was damaged with several teeth missing and one tooth wedged between the forward face of the gear and crankcase. A detailed metallurgical examination of the left idler gear revealed that it failed due to fatigue. Fatigue features were observed at two locations, and both had initiated in the radius between a gear tooth flank and the root. The gears that were engaged with the idler gear were intact and mostly undamaged. The fracture surface at one fatigue location on the left idler gear was much more reflective than the other. A reflective surface, indicative of a rubbing motion of one fracture surface against another, indicates a misalignment of the meshing gears to produce the motion. The fracture surface at the other location was duller, indicating that little or no rubbing occurred, consistent with the fracture occurring after the first fracture with the rubbed surface. The second fracture propagated until the material below the gear teeth could no longer support the stresses of operation and the portion of the gear located between the two fatigue fractures departed the left idler gear. The fatigue was probably initiated by abnormal contact between the left idler gear and the other mating gears, with the relatively recent installation of the left magneto gear being suspect as the likely source of the initiating stressors.
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: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; multi-engine sea; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 5,520 hours in all; 450 in this make and model; 42 in the last 90 days; 31 in the last 30 days; 5,470 as pilot in command; 2,233 on instruments
- Last flight review: March 1, 2006
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 3,326 hours
- Last inspection: annual inspection, February 1, 2007; 124 hours since
- Maximum gross weight: 2,550 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-360-A4M (piston); 0 hours total
The flight
- Departed from: PAE Everett WA
- Destination: YCD Vancouver Islan
- Flight plan: VFR
Weather at the time
- Light: daylight
- Wind: from 190° at 10 knots
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 72°F (22°C), dew point 54°F (12°C)
- Altimeter: 29.85 inHg
- Observation at 5:30 pm from ORS, 13 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.