Aviat A1 accident near Ennis, Montana, July 17, 2019
On July 17, 2019 at about 2:28 pm local time, a 1999 Aviat A1, registered N137C, was destroyed in an accident during maneuvering (low-alt flying) near Ennis, Montana. It was flown under charter and air-taxi rules (Part 135). 2 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's exceedance of the airplane's critical angle of attack while turning at low altitude, which resulted in an aerodynamic stall. Contributing to the accident was the pilot's distraction due to looking at wildlife.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 17, 2019 · about 2:28 pm local time
- Place
- Ennis, Montana · map
- Type
- Accident
- Injuries
- 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Aviat A1 A, built 1999
- Registration
- N137C · no longer on the register · serial 1453
- Damage
- Destroyed
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that he was conducting an aerial survey to spot bears. After spotting bears, he flew multiple low-altitude passes to maintain sight of the bears. While maneuvering uphill at a low altitude, his attention was drawn to the bears and away from terrain. When he regained focus, he decided to turn the airplane right, away from rising terrain, but about 90º into the turn, the airplane descended and impacted terrain, and a postcrash fire ensued. The airplane sustained substantial damage to the wings and fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The pilot added that he should have let the observer observe the bears during the low passes.
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
- Aerodynamic stall/spin during maneuvering (low-alt flying) defining event
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (low-alt flying)
The NTSB's findings
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Angle of attack › Capability exceeded
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- factor Personnel issues › Psychological › Attention/monitoring › Attention › Pilot
Pilot
- Certificate: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane single-engine; instructor: glider; instructor: helicopter; instructor: instrument airplane; instructor: instrument helicopter; instrument: airplane; instrument: helicopter; rotorcraft: glider; rotorcraft: helicopter
- Flight time: 18,000 hours in all; 500 in this make and model; 120 in the last 90 days; 40 in the last 30 days; 17,500 as pilot in command; 2,500 on instruments
- Last flight review: April 4, 2019
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: frt
- Injury: minor injuries
The aircraft
- Airframe total time: 3,525 hours
- Last inspection: 100-hour inspection, June 20, 2019
- Maximum gross weight: 1,890 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-360-AIP (piston); 3,525 hours total
- Fire on the ground
The flight
- Departed from: BZN Bozeman MT at 12:00 pm
- Destination: BZN Bozeman MT
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 70°F (21°C), dew point 0°F (-18°C)
- Observation at 1:53 pm from KRXE, 37 miles away
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 January 9, 2020. 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 | Accident Photo | PDF, 1 page | 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.