Cessna 150M accident near Marion, Wisconsin, October 8, 1991
On October 8, 1991 at about 5:20 pm local time, a Cessna 150M, registered N704CW, was substantially damaged in an accident near Marion, Wisconsin. It was an instructional flight under general aviation rules (Part 91). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE FAILURE OF THE EXHAUST AND INTAKE VALVES. FACTORS CONTRIBUTING TO THE ACCIDENT WERE DOWNHILL TERRAIN AND A COLLAPSED NOSEGEAR.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- October 8, 1991 · about 5:20 pm local time
- Place
- Marion, Wisconsin · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 150M · all 150Ms on the register
- Registration
- N704CW · no longer on the register · serial 15078515
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE STUDENT PILOT WAS FLYING A SINGLE ENGINE AIRPLANE ON A SOLO CROSS COUNTRY FLIGHT WHEN THE ENGINE BEGAN TO RUN ROUGH. THE ENGINE LOST APPROXIMATELY 25 PERCENT OF THE ORIGINAL POWER SETTING. THE AIRPLANE WOULD NOT MAINTAIN ALTITUDE AND WAS, ACCORDING TO THE PILOT, 'VIBRATING VERY BADLY.' THE PILOT CHOSE A FIELD WHICH HE BELIEVED SMOOTH AND LEVEL. UPON TOUCHDOWN THE AIRPLANE ROLLED DOWN HILL AND NOSED OVER AT THE BOTTOM OF THE HILL AFTER ITS NOSEGEAR COLLAPSED. INSPECTION OF THE ENGINE REVEALED FAILED INTAKE AND EXHAUST VALVES, AND A PISTON WITH HOLES IN ITS TOP. THE AIRPLANE WAS OPERATING UNDER AND AUTO GAS STC WHICH ALLOWED THE USE OF THAT FUEL AND ANY MIXTURE COMBINATION OF 100 LL AVIATION FUEL.
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: student
- Flight time: 41 hours in all; 41 in this make and model
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 1,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Continental O-200 A (piston); 0 hours total
The flight
- Destination: 92G Pulaski WI
- Flight plan: VFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 220° at 13 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 1,700 ft; not recorded at 1,700 ft
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
- Observation at 6:50 pm from GRB, 30 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.