Cessna 172N accident near Rochester, Massachusetts, July 12, 2009
On July 12, 2009 at about 4:45 pm local time, a Cessna 172N, registered N4773G, was substantially damaged in an accident during enroute (cruise) near Rochester, Massachusetts. It was a personal flight under general aviation rules (Part 91). No one was hurt; 4 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
An engine vibration as reported by the pilot, for undetermined reasons.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 12, 2009 · about 4:45 pm local time
- Place
- Rochester, Massachusetts · map
- Type
- Accident
- Injuries
- No one was hurt; 4 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172N · all 172Ns on the register
- Registration
- N4773G · no longer on the register · serial 17273342
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that the airplane was in cruise flight when the engine developed sporadic engine vibrations. Manipulation of the carburetor heat and mixture controls did not remedy the situation and the engine subsequently developed a severe vibration. The pilot then elected to reduce engine power and perform a precautionary landing to a field. The airplane touched down in a cranberry bog, and sustained substantial firewall and airframe damage. Examination of the wreckage did not reveal any mechanical malfunctions. It was noted that the No. 2 cylinder lower spark plug was fouled and that the compression on the No. 4 cylinder was lower than that of cylinders 1, 2 and 3; however, the reason for the severe engine vibration could not be determined. The airplane had been operated for approximately 74 hours since its most recent 100 hour inspection, which was performed about two months prior to the accident.
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
What happened, in order
- Powerplant sys/comp malf/fail during enroute (cruise) defining event
- Off-field or emergency landing during emergency descent
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Environmental issues › Physical environment › Runway/land/takeoff/taxi surfa › (general) › Not specified
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 61 hours in all; 61 in this make and model; 4 in the last 90 days; 1 in the last 30 days; 17 as pilot in command
- Last flight review: December 13, 2008
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 5,385 hours
- Last inspection: 100-hour inspection, May 12, 2009; 75 hours since
- Maximum gross weight: 2,300 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-320-H2AD (piston); 0 hours total
- Operator: New England Flight Operations LLC
The flight
- Departed from: ASH Nashua NH at 3:40 pm
- Destination: MVY Vineyard Haven MA
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: broken clouds at 2,300 ft
- Temperature: 75°F (24°C), dew point 64°F (18°C)
- Altimeter: 29.87 inHg
- Observation at 3:53 pm from EWB, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 3 |
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.