- Date
- June 24, 2025, 18:00 local (Jun 25, 2025, 02:00 UTC)
- Place
- Denali Park, AK
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N2655DCessna 170B
- Defining event
- Landing-landing roll: Sys/Comp malf/fail (non-power)
- Weather
- Visual (VMC) · Day
- Status
- Completed · report January 9, 2026
- Report
- Approved by Office Director
- Investigation class
- Class 4 - Basic report with no Prelim publish
- NTSB office
- Alaska Regional Office
- Parties
- FAA - FSDO
- FAA report
- 20250624009889A
- Case key
- 200423
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 failure of the left main landing gear spring due to a fatigue fracture during landing on uneven terrain.
Findings · 5
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, during the landing roll in a tailwheel-equipped airplane on a remote airstrip, he encountered a depression in the landing surface, resulting in the separation of the left main wheel. The left main landing gear leg subsequently dug into the ground and folded back against the fuselage, which caused substantial damage to the fuselage near the main landing gear attach points. After exiting the airplane, the pilot observed that the left main gear leg had fractured above the axle bolts, and the tire, axle, and lower portion of the main landing gear spring had separated from the airplane. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. Photos of the fracture surfaces from the main landing gear spring were examined by the NTSB Materials Laboratory. The features observed were consistent with a fatigue fracture and corrosion. It is likely that a fatigue crack initiated due to corrosion damage at the fracture origin.
Aircraft
- Registration
- N2655D
- Reported as
- Cessna 170B
- Category
- Airplane
- Serial number
- 20807
- Built
- 1956
- Airframe hours
- 5,487.5
- Engine
- Franklin 6A-350-C2, 220 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Personal · Part 91
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · January 18, 2025 · 64 hours before
- Departed
- 5Z5 · Kantishna, AK
- Destination
- Same as departure
- Flight plan
- Company VFR
- Airport
- NONE · Backcountry Airstrip
- Equipment
- Stall warning system
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
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 36
- Injuries
- None
- Certificate
- Commercial
- Airplane ratings
- Multi-engine land, Single-engine land
- Instrument ratings
- Airplane
- Medical
- Class 1, Without waivers/limitations
- Last flight review
- June 8, 2025
- Seat
- Left
- Restraint
- 3-point
- Flight hours
- 3,366.9 total · 478 in this make and model · 3,319 as pilot in command · 255 in the last 90 days · 80.6 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 32 °F, dew point 32 °F
- Altimeter
- 29.68 inHg
- Observed at
- AIN, 62 nm away
- METAR
- PAIN 250156Z AUTO VRB03KT 10SM CLR A2968 RMK AO2 SLPNO FZRANO TSNO $
Docket · 3
The files NTSB released with the investigation on January 9, 2026, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.3 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.