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Registered aircraft · FAA record as of September 25, 2026
N4123D

Helio H-391B

N4123D is a Helio H-391B, a fixed-wing airplane with one motor with a piston engine, built in 1957. It has 4 seats. It is registered to an individual in Graham, Washington. The registration is valid: it was issued on March 3, 1978 and expires on February 28, 2030. It holds a standard airworthiness certificate, dated March 26, 1957.

Aircraft

Maker
Helio
Model
H-391B
Serial number
042
Type
Fixed-wing, single engine
Power
Piston (reciprocating), 1 motor · Lycoming GO-435C&D SER · 260 hp
Seats
4
Year built
1957
Cruising speed
117 mph
Transponder code
A4DE53 (octal 51157123)

Registration

Status
Valid registration
Certificate issued
March 3, 1978
Expires
February 28, 2030
Last FAA action
October 7, 2023
Airworthiness
Standard · March 26, 1957
FAA region
Northwest Mountain
FAA record id
00741424

Owner as the FAA publishes it

Name
Thun Karl J
Type
Individual
Address
PO Box 10
Graham, WA 98338

Owners can ask the FAA to withhold their name and address from public files. When they do, those fields are blank here as well. How that works.

Documents on file 0

No bills of sale, loans or other documents are indexed against this tail number.

Source: FAA Civil Aviation Registry, Releasable Aircraft Database, September 25, 2026. See this record on the FAA site · This record as data