- Date
- May 10, 2026, 12:14 local (18:14 UTC)
- Place
- Marysvale, UT
- Injuries
- 1 serious, 1 minor
- Damage
- Destroyed
- Phase of flight
- Maneuvering
- Aircraft
- N6643ACessna 172
- Defining event
- Maneuvering-low-alt flying: Low altitude operation/event
- Weather
- Visual (VMC) · Day
- Status
- Completed · report July 30, 2026
- Report
- Approved by Office Director
- Investigation class
- Class 4 - Basic report with no Prelim publish
- NTSB office
- Western Pacific Region
- Parties
- FAA
- FAA report
- 20260510006639A
- Case key
- 202970
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot's failure to maintain clearance from trees while maneuvering in mountainous terrain prior to encountering a downdraft.
Findings · 3
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
The pilot reported that while flying along the west side of Monroe Mountain about 1,000 ft above ground level, the airplane encountered a downdraft near a river drainage at the southern end of the valley. The pilot applied full engine power, maneuvered to avoid a tree near the right wingtip, and attempted to maintain airspeed. During the maneuver, the airplane collided with another tree that the pilot had not seen. The airplane subsequently impacted terrain and was consumed by a postimpact fire. The pilot reported that there were no mechanical malfunctions or failures with the airplane that would have precluded normal operation.
Aircraft
- Registration
- N6643A
- Reported as
- Cessna 172
- Category
- Airplane
- Serial number
- 28743
- Built
- 1956
- Airframe hours
- 1,130.3
- Engine
- Continental O-300-B, 145 horsepower, reciprocating
- Damage
- Destroyed
- Fire
- On-Ground
- Flight
- Personal · Part 91
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · October 1, 2025
- Departed
- RIF · Richfield, UT
- Airport
- None · Draw on the west side of mountains
- Equipment
- Stall warning system, Electronic multifunction display
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew · 2
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 87
- Injuries
- Serious
- Airplane ratings
- Single-engine land
- Medical
- Sport pilot, Unknown
- Seat
- Left
- Restraint
- 3-point
- Flight hours
- 2,600 total · 3 in this make and model · 2,600 as pilot in command · 0 in the last 90 days · 0 in the last 30 days · 0 in the last 24 hours
- Role
- Pilot-rated passenger
- Injuries
- Minor
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- BasicMed, With waivers/limitations
- Seat
- Right
- Restraint
- 3-point
- Flight hours
- 400 total
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 20° at 10 knots, gusting 20
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 75 °F, dew point 7 °F
- Altimeter
- 30.20 inHg
- Observed at
- MLF, 41 nm away
- METAR
- METAR KMLF 101752Z AUTO 02010G20KT 10SM CLR 24/M14 A3020 RMK AO2 SLP174 T02441139 10250 20028 56
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.