Monocoupe Aircraft 70 accident near New Holstein, Wisconsin, July 31, 1998
On July 31, 1998 at about 4:30 pm local time, a Monocoupe Aircraft 70, registered NC6740, was substantially damaged in an accident near New Holstein, Wisconsin (New Holstein airport). It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to use carburetor heat in weather conditions conducive to carburetor icing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 31, 1998 · about 4:30 pm local time
- Place
- New Holstein, Wisconsin · New Holstein · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Monocoupe Aircraft 70
- Registration
- NC6740 · no longer on the register · serial 151
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot said that after takeoff, and over the departure end of the runway, the engine began to run rough and lose power. The pilot said that he leaned the mixture. It seemed to help, but then the engine began to run rough again. The pilot turned back toward the airport with the intent of landing on the grassy field near the runway. Then the engine quit. The pilot stretched his glide so that he could clear trees on the edge of a corn field. The pilot tried to force land the airplane in the corn field. The airplane touched down in the corn and flipped over. Examination of the airplane revealed no anomalies. According to the Department of Transportation/Federal Aviation Administration/CT-82/44 Publication: Light Aircraft Piston Engine Carburetor Ice Detector/Warning Device Sensitivity/Effectiveness, June 1982, Carburetor Icing Probability Chart; the temperature (72 degrees Fahrenheit) and dew point (52 degrees Fahrenheit) at the time the airplane lost power, places the probability for carburetor icing in the 'serious icing at glide power' area of the chart.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 5,000 hours in all; 40 in this make and model
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: frt
The aircraft
- Airframe total time: 300 hours
- Last inspection: annual inspection, March 30, 1998
- Maximum gross weight: 1,299 lb
- Seats: 1
- Landing gear: fixed
- Engine: Velie (piston); 0 hours total
The flight
- Departed from: 8D1 at 4:30 pm
- Destination: OSH Oshkosh WI
- Flight plan: none
- Runway 32, 3,600 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 020° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 72°F (22°C), dew point 52°F (11°C)
- Altimeter: 30.00 inHg
- Observation at 4:53 pm from FLD, 19 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.