sensors Mode-S transponder

A5FE17

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N4854G · CESSNA 172 Skyhawk · operated by MILWAUKEE AERO LLC

Hex
A5FE17
Octal
51377027
Decimal
10,878,487
Country
US
Tail
N4854G
Type
C172
No current signal · last broadcast 23h ago
Flights observed
5
Distinct callsigns
1
Country
US
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S A5FE17.

Country allocation

The ICAO 24-bit address A5FE17 falls within the block assigned to United States (US) by ICAO Annex 10, Volume III. Every aircraft registered in United States receives a permanent address from this block at the time of registration; the address stays with the airframe even if the aircraft is re-registered to a different operator within the country.

Callsign history 1 distinct

Callsign Airline Flights Last seen
N4854G - 5 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 N4854G - Apr 13, 22:50 UTCApr 13, 23:40 UTC50m
2026-04-13 N4854G - Apr 13, 16:15 UTCApr 13, 16:25 UTC10m
2026-04-13 N4854G - Apr 13, 15:50 UTCApr 13, 16:25 UTC35m
2026-04-13 N4854G - Apr 13, 14:55 UTCApr 13, 16:15 UTC1h 20m
2026-04-12 N4854G - Apr 12, 17:15 UTCApr 12, 17:50 UTC35m

About Mode-S

A Mode-S transponder code (also called an "ICAO 24-bit address" or "hex code") is a 6-character hexadecimal identifier permanently assigned to an aircraft when it's first registered. Unlike callsigns (which change with each flight) or registrations (which can change if an aircraft is sold internationally), the Mode-S address stays with the airframe for the life of the aircraft in that country.

Every ADS-B transmission from an aircraft includes its Mode-S address, making it the most reliable way to identify a specific airframe. Flight-tracking services like Apparatus use the Mode-S address as the primary key for tying position broadcasts, callsigns, and ownership records together.

Prefer a tail-number view? See the N4854G page for operator, model, and routing details .

Mode-S A5FE17 frequently asked

What is Mode-S code A5FE17?
A5FE17 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N4854G.
Where is Mode-S A5FE17 registered?
Mode-S code A5FE17 is allocated to United States (US). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is A5FE17 broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A5FE17, octal 51377027, decimal 10,878,487.
What flights does A5FE17 operate?
Mode-S A5FE17 has broadcast 1 distinct callsign, including N4854G.