sensors Mode-S transponder

A9AB87

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N722FR · AIRBUS A-321 · operated by ALC A321 8579 LLC

Hex
A9AB87
Octal
52325607
Decimal
11,119,495
Country
US
Tail
N722FR
Type
A321
No current signal · last broadcast 1d ago
Flights observed
8
Distinct callsigns
6
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S A9AB87.

Country allocation

The ICAO 24-bit address A9AB87 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 6 distinct

Callsign Airline Flights Last seen
FFT2800 - 2 2026-04-13
FFT2799 - 2 2026-04-13
FFT45 - 1 2026-04-12
FFT3243 - 1 2026-04-13
FFT2198 Frontier Airlines 1 2026-04-13
FFT1342 - 1 2026-04-13

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-13 FFT2198 ORD → ATL Apr 13, 21:45 UTCApr 13, 23:15 UTC1h 30m
2026-04-13 FFT1342 DFW → ORD Apr 13, 17:46 UTCApr 13, 19:34 UTC1h 48m
2026-04-13 FFT3243 - Apr 13, 13:40 UTCApr 13, 15:35 UTC1h 55m
2026-04-13 FFT2800 - Apr 13, 04:20 UTCApr 13, 06:40 UTC2h 20m
2026-04-13 FFT2800 AUS → ORD Apr 13, 04:10 UTCApr 13, 06:40 UTC2h 30m
2026-04-13 FFT2799 - Apr 13, 00:20 UTCApr 13, 02:20 UTC2h 0m
2026-04-12 FFT2799 - Apr 12, 23:55 UTCApr 13, 02:20 UTC2h 25m
2026-04-12 FFT45 - Apr 12, 18:00 UTCApr 12, 21:01 UTC3h 1m

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 N722FR page for operator, model, and routing details .

Mode-S A9AB87 frequently asked

What is Mode-S code A9AB87?
A9AB87 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N722FR.
Where is Mode-S A9AB87 registered?
Mode-S code A9AB87 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 A9AB87 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A9AB87, octal 52325607, decimal 11,119,495.
What flights does A9AB87 operate?
Mode-S A9AB87 has broadcast 6 distinct callsigns, including FFT2800, FFT2799, FFT45, FFT3243, FFT2198.