sensors Mode-S transponder

AC79A3

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N9025B · AIRBUS A-319 · operated by UMB BANK NA TRUSTEE

Hex
AC79A3
Octal
53074643
Decimal
11,303,331
Country
US
Tail
N9025B
Type
A319
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
4
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AC79A3.

Country allocation

The ICAO 24-bit address AC79A3 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 4 distinct

Callsign Airline Flights Last seen
AAL2957 - 2 2026-04-13
AAL2604 - 2 2026-04-13
AAL2058 American Airlines 1 2026-04-13
AAL1934 American Airlines 1 2026-04-12

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 AAL2957 BUF → ORD Apr 13, 20:20 UTCApr 13, 21:40 UTC1h 20m
2026-04-13 AAL2957 ORD → BUF Apr 13, 17:25 UTCApr 13, 18:35 UTC1h 10m
2026-04-13 AAL2058 SNA → DFW Apr 13, 13:00 UTCApr 13, 15:25 UTC2h 25m
2026-04-13 AAL2604 - Apr 13, 00:20 UTCApr 13, 00:55 UTC35m
2026-04-12 AAL2604 - Apr 12, 23:55 UTCApr 13, 00:55 UTC1h 0m
2026-04-12 AAL1934 LGA → RDU Apr 12, 18:40 UTCApr 12, 19:05 UTC25m

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 N9025B page for operator, model, and routing details .

Mode-S AC79A3 frequently asked

What is Mode-S code AC79A3?
AC79A3 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N9025B.
Where is Mode-S AC79A3 registered?
Mode-S code AC79A3 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 AC79A3 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 AC79A3, octal 53074643, decimal 11,303,331.
What flights does AC79A3 operate?
Mode-S AC79A3 has broadcast 4 distinct callsigns, including AAL2957, AAL2604, AAL2058, AAL1934.