Aviat Aircraft INC A 1B accident near Prairie Du Chien, Wisconsin, September 9, 2017
On September 9, 2017 at about 8:45 pm local time, a 2005 Aviat Aircraft INC A 1B, registered N299CA, was substantially damaged in an accident during enroute near Prairie Du Chien, Wisconsin (Prairie Du Chien Muni airport). It was a business 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 fatigue failure of the aileron hinge bracket tubing for reasons that could not be determined based on the available evidence.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 9, 2017 · about 8:45 pm local time
- Place
- Prairie Du Chien, Wisconsin · Prairie Du Chien Muni · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Aviat Aircraft INC A 1B, built 2005 · all A 1Bs on the register
- Registration
- N299CA · registry record · serial 2294
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
Following the aerial photography portion of the flight, the commercial pilot climbed the airplane to 3,500 ft mean sea level and proceeded toward the destination. About 5 minutes later, he felt "light buffeting" as the airplane rolled left. He attempted to counteract the left roll by applying right control stick pressure, but the airplane continued to roll left. He input right rudder to stop the left roll and decided to return to the airport of origin, 10 nautical miles away. He used the rudder to maneuver the airplane and landed uneventfully. After parking the airplane, he moved the control stick left and right several times and the outboard end of the left aileron fell to the ground. Review of airplane maintenance records revealed that, about 9 years before the accident, the left wing tip was replaced due to "hangar rash," though there was no specific mention of damage to the left aileron. There were no other logbook entries that mentioned the left wing or left aileron. Metallurgical analysis of the aileron hinge bracket revealed two fatigue fracture origins that led to two regions of final overstress fracture. The fatigue fractures occurred under low stress over an extended period of time. No anomalies were noted in the origin regions and there was no specific evidence of bending at the fracture area. Since there was no specific evidence of bending, it could not be determined if the previous damage to the wing tip resulted in unidentified stress to the fracture area. Wing tip damage as a result of hangar rash could have resulted in residual tension in the aileron tube and precipitated the low-stress fatigue fracture; however, the severity of previous damage to the wing tip and whether the aileron was affected could not be determined.
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
- Flight control sys malf/fail during enroute defining event
The NTSB's findings
- cause Aircraft › Aircraft systems › Flight control system › Aileron control system › Fatigue/wear/corrosion
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 19,430 hours in all; 16,000 in this make and model; 353 in the last 90 days; 115 in the last 30 days; 19,330 as pilot in command; 248 on instruments
- Last flight review: April 13, 2017
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 5,779 hours
- Last inspection: annual inspection, January 24, 2017
- Maximum gross weight: 2,000 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-360-A1P (piston); 5,779 hours total
The flight
- Departed from: PDC Prairie Du Chien WI at 6:00 pm
- Destination: LSE La Crosse WI
- Flight plan: none
- Runway 11, 3,999 ft by 75 ft
Weather at the time
- Light: daylight
- Wind: from 130° at 8 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 52°F (11°C)
- Altimeter: 30.29 inHg
- Observation at 8:55 pm from KPDC
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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 N299CA 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.