Textron Aviation INC 172S accident near Eden, Utah, May 29, 2021
On May 29, 2021 at about 4:00 pm local time, a 2017 Textron Aviation INC 172S, registered N1727T, was destroyed in an accident during enroute (change of cruise level) near Eden, Utah. It was an instructional flight under general aviation rules (Part 91). 2 people were killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The flight instructor’s improper aeronautical decision-making, which led to an encounter with a downdraft at a low altitude in mountainous terrain and resulted in the instructor’s loss of airplane control and an impact with terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 29, 2021 · about 4:00 pm local time
- Place
- Eden, Utah · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Textron Aviation INC 172S, built 2017
- Registration
- N1727T · no longer on the register · serial 172S12056
- Damage
- Destroyed
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The flight instructor departed on an introductory training flight with a prospective student and initially flew a standard flightpath for this type of flight. At some point, the instructor, elected to enter a canyon presumably to overfly a nearby mountain The airplane entered the canyon initially with about 1,000 ft of clearance above the terrain but then impacted rising terrain about 2 to 3 minutes later when the airplane was about 2 miles into the canyon. Postaccident examination of the wreckage revealed no preimpact mechanical anomalies that would have precluded normal operation. Performance computations showed that the airplane should have been able to successfully climb out of the canyon. However, meteorological evidence indicated that the airplane likely encountered a downdraft and possible mountain wave conditions near the canyon. Specifically, the wind profile over the canyon was favorable for mountain wave conditions with downdrafts of about 500 ft per minute at an altitude of about 10,000 ft mean sea level. Although the altitude in the profile was above the airplane’s last recorded altitude, the airplane likely still encountered a downdraft given that the flight instructor was able to tell a sheriff’s deputy (immediately after the accident) that he “got caught in a downdraft.” Thus, a downdraft likely resulted in a loss of control and the airplane’s impact with terrain. Although the accident pilot had limited experience as a flight instructor at the time of the accident, he possessed the basic airmanship skills required for the flight. However, the instructor demonstrated improper aeronautical decision-making when he decided to enter the mountainous area, especially given that the operator did not provide its flight instructors with any practical mountain flight training. Other company flight instructors reported that they would not have entered that area during introductory training flights. The accident flight was the fifth introductory training flight that the flight instructor conducted but the first that was operated over the mountainous area. The reason that the flight instructor decided to operate in the mountainous area could not be determined from the available evidence. Nevertheless, by entering the mountainous area unnecessarily, the flight instructor placed the airplane in a hazardous situation that ultimately led to downdraft encounter from which he could not recover. Postmortem toxicology testing of the pilot’s blood detected multiple medications commonly administered for resuscitation or severe pain management: ketamine, norketamine, propofol, morphine, fentanyl, norfentanyl, lorazepam, and midazolam. The investigation determined that the ketamine, norketamine, fentanyl, norfentanyl, midazolam, morphine and lorazepam were likely administered during life-saving efforts. Propofol is a short-acting anesthetic administered by hospital anesthetists. Thus, the identified medications were likely administered post-accident and did not contribute to the accident.
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 enroute (change of cruise level) defining event
- Windshear or thunderstorm during enroute (change of cruise level)
The NTSB's findings
- Environmental issues › Conditions/weather/phenomena › Wind › Downdraft › Ability to respond/compensate
- Environmental issues › Conditions/weather/phenomena › Wind › Downdraft › Availability of related info
- Environmental issues › Physical environment › Terrain › Mountainous/hilly terrain › Effect on operation
- Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
Flight instructor
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane
- Flight time: 311 hours in all; 311 in this make and model
- Last flight review: August 28, 2020
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: rear
- Injury: fatal
The aircraft
- Airframe total time: 3,006 hours
- Last inspection: 100-hour inspection, April 13, 2021; 91.1 hours since
- Maximum gross weight: 2,550 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-360-L2A (piston); 575 hours total
- Not recorded
- Operator: Flight Operations Aircraft LLC
The flight
- Departed from: OGD Ogden UT at 3:30 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Temperature: 64°F (18°C), dew point 25°F (-4°C)
- Altimeter: 30.07 inHg
- Observation at 9:53 am from KOGD, 15 miles away
Weather report (METAR): KOGD 291553Z VRB04KT 10SM CLR 18/M04 A3007 RMK AO2 SLP135 T01781039
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
22 documents, released by the NTSB on December 15, 2022. 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.
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.
