Boeing A-75 accident near La Crosse, Wisconsin, August 20, 2003
On August 20, 2003 at about 3:15 pm local time, a Boeing A-75, registered N806RB, was substantially damaged in an accident near La Crosse, Wisconsin (La Crosse Muni airport). It was a personal 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 total loss of engine power due to a fatigue fracture of the engine's crankshaft. A factor was the corn crop.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 20, 2003 · about 3:15 pm local time
- Place
- La Crosse, Wisconsin · La Crosse Muni · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Boeing A-75 · all A-75s on the register
- Registration
- N806RB · registry record · serial 75-4000
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The airplane sustained substantial damage when it nosed over during a forced landing to a cornfield after a total loss of engine power. The pilot reported the engine "suddenly began vibrating." The engine seized and the propeller stopped turning 10 seconds after the vibration started. He executed a forced landing to a cornfield, and the airplane nosed over during landing roll. The inspection revealed that the crankshaft was fractured in two pieces, with the fracture between the crankshaft rod journal and the front main bearing. Fatigue stress crack progression was observed on approximately 50 percent of the fracture surface. The cracking appeared to originate in the forward radius of the master-rod bearing journal. The remainder of the fracture surface exhibited conditions typical of tensile overload. The reason for the initiation of the crack in the journal radius of the crankshaft was not identified. The engine manufacturer's recommended time between overhaul (TBO) for the R-985 engine is 1,600 hours. The operator imposed a 1,200 hour TBO on the engines used in its fleet of airplanes.
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; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 17,526 hours in all; 10,781 in this make and model; 168 in the last 90 days; 63 in the last 30 days; 16,931 as pilot in command; 5,993 on instruments
- Last flight review: December 31, 2002
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rear
- Injury: no injuries
The aircraft
- Airframe total time: 11,673 hours
- Last inspection: 100-hour inspection, August 1, 2003; 20 hours since
- Maximum gross weight: 3,520 lb
- Seats: 2
- Landing gear: fixed
- Engine: Pratt & Whitney R-985 (piston); 0 hours total
The flight
- Departed from: MWC Milwaukee WI at 1:45 pm
- Destination: LSE La Crosse WI
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 210° at 12 knots
- Visibility: 9 statute miles
- Sky: clear
- Temperature: 90°F (32°C), dew point 73°F (23°C)
- Altimeter: 29.89 inHg
- Observation at 4:53 pm from LSE, 3 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.
Other NTSB records under N806RB the same tail number, which may have belonged to a different aircraft at the time
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.