sensors Mode-S transponder

A3A9AF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N335PH · BOEING 737-800 · operated by AMERICAN AIRLINES INC

Hex
A3A9AF
Octal
50724657
Decimal
10,725,807
Country
US
Tail
N335PH
Type
B738
Photo of N335PH
Broadcasting now · callsign AAL1060 · 19,625 ft
Flights observed
7
Distinct callsigns
3
Country
US
Last broadcast
23h ago

Current position

A3A9AF is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A3A9AF 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 3 distinct

Callsign Airline Flights Last seen
AAL1799 American Airlines 4 2026-04-13
AAL1263 - 2 2026-04-13
AAL2739 - 1 2026-04-12

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-13 AAL1263 - Apr 13, 20:05 UTCApr 13, 23:25 UTC3h 20m
2026-04-13 AAL1263 - Apr 13, 18:24 UTCApr 13, 21:24 UTC3h 0m
2026-04-13 AAL1799 LAX → PHL Apr 13, 16:15 UTCApr 13, 16:30 UTC15m
2026-04-13 AAL1799 LAX → PHL Apr 13, 15:50 UTCApr 13, 16:30 UTC40m
2026-04-13 AAL1799 LAX → PHL Apr 13, 15:02 UTCApr 13, 16:31 UTC1h 29m
2026-04-13 AAL1799 LAX → PHL Apr 13, 12:20 UTCApr 13, 13:45 UTC1h 25m
2026-04-12 AAL2739 - Apr 12, 17:07 UTCApr 12, 19:24 UTC2h 17m

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 N335PH page for operator, model, and routing details .

Mode-S A3A9AF frequently asked

What is Mode-S code A3A9AF?
A3A9AF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N335PH.
Where is Mode-S A3A9AF registered?
Mode-S code A3A9AF 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 A3A9AF broadcasting right now?
Yes. Mode-S A3A9AF is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A3A9AF, octal 50724657, decimal 10,725,807.
What flights does A3A9AF operate?
Mode-S A3A9AF has broadcast 3 distinct callsigns, including AAL1799, AAL1263, AAL2739.