Amateur-built HIGHLANDER accident near Oshkosh, Wisconsin, July 20, 2024
On July 20, 2024 at about 10:21 pm local time, a 2024 amateur-built HIGHLANDER, registered N707KM, was substantially damaged in an accident during landing (flare/touchdown) near Oshkosh, Wisconsin (Wittman Rgnl airport). It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The reported uncommanded retraction of the flaps while on short final for unknown reasons, which resulted in a hard landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 2024 · about 10:21 pm local time
- Place
- Oshkosh, Wisconsin · Wittman Rgnl · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built HIGHLANDER JA20, built 2024
- Registration
- N707KM · registry record · serial JA592-07-20
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that when the airplane was on short final to land on a grass airstrip, close to the ground, the wing flaps retracted from 40° to 0° uncommanded, and the airplane started to sink. The pilot added engine power to arrest the descent; however, the airplane landed hard. The pilot taxied the airplane without further incident. A postlanding examination of the airframe revealed substantial damage to the fuselage on the right side. After the accident, the flaps were manipulated in and out of the fully extended flap position using the flap actuator handle. The flap controls were continuous and extended and retracted as designed. The flap actuator handle always remained secure in the detent. Investigators were unable to duplicate the uncommanded retraction of the flaps from 40° to 0°. There were no mechanical anomalies with the airplane or related systems that would have precluded normal operations.
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
- Hard landing during landing (flare/touchdown) defining event
The NTSB's findings
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Landing flare › Not attained/maintained
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 682 hours in all; 60 in this make and model; 270 in the last 90 days; 113 in the last 30 days; 600 as pilot in command
- Last flight review: March 18, 2024
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 50 hours
- Last inspection: condition inspection, July 1, 2024
- Maximum gross weight: 1,550 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotax 915 (piston); 0 hours total
The flight
- Departed from: Valparaiso IN at 7:50 pm
- Flight plan: none
- Runway 33, 1,200 ft by 25 ft
Weather at the time
- Light: daylight
- Wind: at 5 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 7,000 ft
- Temperature: 81°F (27°C), dew point 61°F (16°C)
- Altimeter: 30.06 inHg
- Observation at 5:53 pm from KOSH
Weather report (METAR): METAR KOSH 202253Z VRB05KT 10SM BKN070 27/16 A3006 RMK AO2 SLP168 T02720156=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
5 documents, released by the NTSB on June 4, 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, 11 pages | View Download |
| 2 | Passenger Statement | PDF, 1 page | View Download |
| 3 | Examination Summary Statement | PDF, 2 pages | View Download |
| 4 | Maintenance Records | PDF, 4 pages | View Download |
| 5 | Video - Specialist's Factual Report | PDF, 4 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.