# Accident 20250818013389A: Helio H-391B, Monroe, MI, August 18, 2025

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: August 18, 2025, 12:34 local time
- Place: Monroe, MI
- Airport: Custer
- Damage: Substantial damage
- Phase of flight: Landing: Touchdown
- Operating rules: General operating rules (Part 91)
- Location: 41.9399° N, 83.4347° W: From the FAA
- Nearby events: https://openairdocs.org/map.md?lat=41.9399&lon=-83.4347&mi=10
- Aircraft: N4431U, registered now (https://openairdocs.org/aircraft/N4431U) (OpenAirDocs)
- Registry model: Helio H-391B (registry code 4300106, https://openairdocs.org/model/helio-h-391b) (OpenAirDocs)
- Reported make and model: HELIO H-391B
- People aboard: 2
- Fatal injuries: 0
- Other injuries: 0
- Pilot certificates: Private pilot
- Pilot flight hours: 12 in this make and model, 12 in the last 90 days
- NTSB investigation: [NTSB CEN25LA325](https://openairdocs.org/ntsb/CEN25LA325) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/20250818013389A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

PILOT LOST CONTROL ATTEMPTING TO LAND WITH A CROSSWIND. THE AIRCRAFT TURNED 90 DEGREES RIGHT INTO THE WIND AND SKIDDED ON THE LEFT MAIN WHEEL. UPON EXITING THE RUNWAY AND COMING INTO CONTACT WITH THE GRASS, THE LEFT MAIN LANDING GEAR SNAPPED OFF AND THE AIRCRAFT CAME TO REST 180 DEGREES ON THE FUSELAGE AND LEFT WING, RESULTING IN CRINKLING OF THE WING AND PROPELLER CONTACT WITH THE GROUND. THE PROPELLER CONTACT CURLED THE BLADES AND BROKE THE GEAR REDUCTION UNIT AND THE PROPELLER AND HUB SEPARATED FROM THE ENGINE.

## The NTSB's investigation of this event (1)

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [NTSB CEN25LA325](https://openairdocs.org/ntsb/CEN25LA325), Aug 18, 2025: Helio H-391B (N4431U), Monroe, MI, substantial damage. Probable cause: The pilot’s failure to maintain directional control during the landing roll with a crosswind.

## Other reports on N4431U (2)

Matched to the same aircraft by N-number and date.

- [Accident 19920825050879A](https://openairdocs.org/incident/19920825050879A), Aug 25, 1992: Helio H391B (N4431U), Everett, WA, Destroyed. Lost partial power. Unable reach airport. Ditched in bay. NR4 exhaust valve was seized in open position.
- [Accident 19831119063709A](https://openairdocs.org/incident/19831119063709A), Nov 19, 1983: Helio H391B (N4431U), Hood River, OR, Substantial damage. Pilot gound looped aircraft during landing when he attempted high speed turn off of runway.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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