Piper PA-18-150 accident near Wilsall, Montana, April 18, 2021
On April 18, 2021 at about 5:30 pm local time, a 1976 Piper PA-18-150, registered N83359, was substantially damaged in an accident during landing (landing roll) near Wilsall, Montana (Wilsall 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 pilot's failure to maintain directional control during the landing roll with a crosswind.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 18, 2021 · about 5:30 pm local time
- Place
- Wilsall, Montana · Wilsall · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Piper PA-18-150, built 1976 · all PA-18-150s on the register
- Registration
- N83359 · registry record · serial 18-7609099
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot of a tailwheel-equipped airplane reported that, while conducting a wheel landing on a grass runway with a direct crosswind, as the tailwheel settled onto the ground, the airplane veered right. He attempted to correct by applying left brake. Subsequently, the airplane ground looped to the right, substantially damaging the left wing and elevator when they impacted the ground. The pilot reported that there were no pre accident mechanical failures or malfunctions with the airplane that would have precluded normal operation.
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 on ground during landing (landing roll) defining event
- Attempted remediation/recovery during landing (landing roll)
The NTSB's findings
- Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Directional control › Not attained/maintained
- Environmental issues › Conditions/weather/phenomena › Wind › Crosswind › Effect on operation
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 432 hours in all; 66 in this make and model; 4 in the last 90 days; 3 in the last 30 days; 432 as pilot in command; 0 on instruments
- Last flight review: June 5, 2020
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: frt
- Injury: no injuries
Passenger
- Seat: rear
- Injury: no injuries
The aircraft
- Airframe total time: 4,560 hours
- Last inspection: annual inspection, September 11, 2020; 20 hours since
- Maximum gross weight: 1,750 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-B2B (piston); 4,560 hours total
The flight
- Flight plan: none
- Runway 19, 3,100 ft by 78 ft
Weather at the time
- Light: daylight
- Wind: from 280° at 10 knots
- Temperature: 59°F (15°C), dew point 25°F (-4°C)
- Altimeter: 30.11 inHg
- Observation at 11:30 am from KBZM, 25 miles away
Weather report (METAR): SA 18/04/2021 17:56-> METAR KBZN 181756Z VRB06KT 10SM CLR 15/M04 A3011 RMK AO2 SLP190 T01501044 10156 21050 58020=
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on September 21, 2021. 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 | Photos | PDF, 2 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.