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Registered aircraft · FAA record as of September 25, 2026
N85303

Grumman HU-16B

Valid Colorado

N85303 is a Grumman HU-16B, a fixed-wing airplane with more than one motor with a piston engine, built in 1951. It has 8 seats. It is registered to Duckbutt LLC, an LLC in Castle Rock, Colorado. The registration is valid: it was issued on April 18, 2024 and expires on April 30, 2031. It holds an experimental airworthiness certificate for exhibition, dated February 4, 2023.

Aircraft

Maker
Grumman
Model
HU-16B
Serial number
51-5303
Type
Fixed-wing, multi-engine
Power
Piston (reciprocating), 2 motors · Wright R-1820 SER · 1475 hp
Seats
8
Year built
1951
Cruising speed
168 mph
Transponder code
ABB4F1 (octal 52732361)

Registration

Status
Valid registration
Certificate issued
April 18, 2024
Expires
April 30, 2031
Last FAA action
April 18, 2024
Airworthiness
Experimental · Exhibition · February 4, 2023
FAA region
Northwest Mountain
FAA record id
00545042

Owner as the FAA publishes it

Name
Duckbutt LLC
Type
LLC
Address
3855 Ambrosia St Ste 304
Castle Rock, CO 80109-3959

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