Cessna 172B accident near Wiscasset, Maine, September 12, 2004
On September 12, 2004 at about 5:30 pm local time, a Cessna 172B, registered N7422X, was substantially damaged in an accident near Wiscasset, Maine (Wiscasset 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
The failure of the oil filter adapter seal, which resulted in a loss of oil pressure, and subsequent catastrophic engine failure, and forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 12, 2004 · about 5:30 pm local time
- Place
- Wiscasset, Maine · Wiscasset · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172B · all 172Bs on the register
- Registration
- N7422X · registry record · serial 17247922
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
While in cruise flight, the engine suddenly began to lose oil pressure. Thirty seconds later, the engine quit, and the pilot performed a forced landing to a field. During the landing, the airplane struck trees and flipped over. Examination of the engine revealed oil in the engine compartment and an oil leak that originated from the seal where the oil filter adapter attached to the crankcase. A subsequent teardown of the engine reveled that the number 1 connecting rod was fractured and exhibited thermal signatures, consistent with high temperatures. Fragments of bearing and connecting rod material were located in the oil sump. The fragments were blackened, consistent with exposure to high temperatures. In addition, the crankshaft exhibited thermal damage and smearing on the number 1 and number 2 connecting rod journals.
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: 329 hours in all; 229 in this make and model; 38 in the last 90 days; 11 in the last 30 days; 285 as pilot in command
- Last flight review: June 1, 2003
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 4,153 hours
- Last inspection: annual inspection, October 1, 2003
- Maximum gross weight: 2,200 lb
- Seats: 4
- Landing gear: fixed
- Engine: Teledyne Continental O-300D (piston); 0 hours total
The flight
- Departed from: 3B1 Greenville ME at 4:00 pm
- Destination: IWI Wiscasset ME
- Flight plan: none
- Runway 25, 3,397 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 200° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 70°F (21°C), dew point 46°F (8°C)
- Altimeter: 30.14 inHg
- Observation at 5:53 pm from IWI, 3 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.