Amateur-built V-Strut accident near Oshkosh, Wisconsin, July 25, 2023
On July 25, 2023 at about 12:33 pm local time, a 2002 amateur-built V-Strut, registered N9549, was substantially damaged in an accident during initial climb near Oshkosh, Wisconsin (Wittman Regional 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 maintain adequate airspeed and his exceedance of the airplane’s critical angle of attack, which resulted in an aerodynamic stall.
Source: NTSB aviation accident database, copy made November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 25, 2023 · about 12:33 pm local time · cases in 2023
- Place
- Oshkosh, Wisconsin · Wittman Regional Airport · cases near this airport · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built V-Strut, built 2002
- Registration
- N9549 · registry record · serial 151
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
Shortly after takeoff the pilot turned the airplane to avoid flying over the perpendicular runway. He reported that during the turn the airplane stopped climbing. The pilot aimed the airplane toward a field and attempted a forced landing. During the landing the airplane came to rest inverted, which resulted in substantial damage to the fuselage, empennage, and both wings. One witness stated that the airplane “looked sluggish,” with the nose of the airplane high. Several witnesses observed the left wing dip before the airplane descended below the tree line. Security video showed the left wing dropped and the airplane impacted the ground in a left-wing-low attitude. A postaccident examination of the engine, flight controls, and related systems revealed no mechanical failures or malfunctions that would have precluded normal operations. The splintered damage to the propeller blade was consistent with power and rotation at the time of impact. The pilot also reported that there was nothing mechanically wrong with the airplane at the time of the accident. Weather conditions at the time of the accident were conducive for serious icing at glide power. However, investigators were not able to determine if a partial loss of engine power due to the accumulation of carburetor icing during the ground taxi may have resulted in the loss of climb performance after takeoff. Given the witness description and the footage captured by the security camera, it is likely that the pilot failed to maintain adequate airspeed during the initial climb and turn, which resulted in the exceedance of the airplane’s critical angle of attack and an aerodynamic stall and a subsequent loss of control.
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
- Loss of control in flight during initial climb defining event
- Aerodynamic stall/spin during initial climb
- Collision with terrain or object (not controlled flight into terrain) during uncontrolled descent
The NTSB's findings
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Capability exceeded
- Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 213 hours in all; 0.4 in this make and model; 8 in the last 90 days; 1.6 in the last 30 days; 144 as pilot in command
- Last flight review: June 16, 2023
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: sngl
- Injury: serious injuries
The aircraft
- Airframe total time: 100 hours
- Last inspection: condition inspection, August 7, 2022
- Maximum gross weight: 675 lb
- Seats: 1
- Landing gear: fixed
- Engine: Continental A-40 (piston); 0 hours total
The flight
- Departed from: KOSH Oshkosh WI at 12:33 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 4 statute miles
- Sky: clear
- Temperature: 72°F (22°C), dew point 66°F (19°C)
- Altimeter: 30.07 inHg
- Observation at 7:53 am from KOSH
Weather report (METAR): KOSH 251253Z 00000KT 4SM HZ CLR 22/19 A3007 RMK AO2 SLP169 T02170189
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Photographs from the investigation 7 pictures from the NTSB's docket, as the NTSB released them
Photograph 1 – Front view of the accident airplane
Photograph 2 – Right wing of the accident airplane
Photograph 3 – Left wing of the accident airplane
Photograph 4 – Empennage
Photograph 5 – Engine and propeller
Photograph 6 – Left Wing
Photograph 7 – Instrument panelThe NTSB's photographs with the NTSB's captions, at screen size. Open a picture to see it full size or to report one that should not be shown.
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on March 12, 2025. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 9 pages | View Download |
| 2 | Examination Summary Statement | PDF, 3 pages | View Download |
| 3 | Carburetor Icing Probability Chart | PDF, 1 page | View Download |
| 4 | Maintenance Records Excerpts | PDF, 3 pages | View Download |
| 5 | Witness Statement | PDF, 1 page | View Download |
| 6 | Accident Report Photographs | PDF, 8 pages · our copy | View Download |
| 7 | Security Video | video | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Connections how this case links to the rest of the register
- N9549 on the register today · the tail number may have moved to another aircraft since
- Engine: Continental A-40 112 aircraft carry this series today · as the NTSB recorded it
- Wittman Regional · nearest airport
- Wittman Regional · departed from
- Accidents and incidents in Wisconsin 1,622 since 1982 · 226 in the last ten years
- Wisconsin 6,164 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/CEN23FA320.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.
