sensors Mode-S transponder

A8F9FD

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N678FR · operated by FRONTIER AIRLINES INC.

Hex
A8F9FD
Octal
52174775
Decimal
11,074,045
Country
US
Tail
N678FR
No current signal · last broadcast 20h ago
Flights observed
1
Distinct callsigns
1
Country
US
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S A8F9FD.

Country allocation

The ICAO 24-bit address A8F9FD 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
FFT9078 Frontier Airlines 1 2026-05-29

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-05-29 FFT9078 BFM → TPA May 29, 19:40 UTCMay 29, 20:40 UTC1h 0m

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 N678FR page for operator, model, and routing details .

Mode-S A8F9FD frequently asked

What is Mode-S code A8F9FD?
A8F9FD is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N678FR.
Where is Mode-S A8F9FD registered?
Mode-S code A8F9FD 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 A8F9FD broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A8F9FD, octal 52174775, decimal 11,074,045.
What flights does A8F9FD operate?
Mode-S A8F9FD has broadcast 1 distinct callsign, including FFT9078.