Helio H-391B N4431U

Summary

On 18 August 2025 at about 17:30 local time, a Helio H-391B registered N4431U was involved in an accident near Monroe, Michigan, United States. One person was on board and nobody was injured. The aircraft was substantially damaged. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

18 August 2025 at 17:30

Classification

Accident

Location

Monroe, Michigan, United States

Nearest airport

Custer Airport (TTF)

Coordinates

41.9399, -83.4347

Aircraft

Helio H-391B

Registration

N4431U

Category

Airplane

Year built

1958

Engines

1

Operator

Not recorded

Operating rule

Part 91: General Aviation

Purpose of flight

Personal

Phase of flight

Not recorded

Route

Napolean → Monroe

Aircraft damage

Substantial

Weather

VMC

Light

Day

NTSB number

CEN25LA325

Nobody was injured.

The pilot’s failure to maintain directional control during the landing roll with a crosswind.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

The pilot reported that while landing his tailwheel airplane in a crosswind, the airplane bounced upon touchdown. The right wing lifted, the airplane drifted down the runway on the left wheel, and the airplane exited the runway into the grass. The left wheel dug into the grass and the airplane pivoted. During the accident sequence, the left landing gear separated from the fuselage, and the left wing struck the ground. The left wing was substantially damaged. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. At the time of the accident, the pilot was landing the airplane on runway 03 with wind from 100° at 10 knots gusting 15 knots.

Quoted verbatim from the NTSB record.