Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A704F9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N551UW · AIRBUS A-321 · operated by UMB BANK N A TRUSTEE

Hex
A704F9
Octal
51602371
Decimal
10,945,785
Country
US
Tail
N551UW
Type
A321
Broadcasting now · callsign AAL536 · 18,475 ft
Flights observed
385
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 22:10 UTC

Current position

A704F9 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A704F9 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 20 distinct

Callsign Airline Flights Last seen
AAL2947 - 7 2026-07-19
AAL863 - 4 2026-07-06
AAL402 - 4 2026-07-09
AAL3064 American Airlines 4 2026-07-23
AAL2762 American Airlines 4 2026-06-15
AAL1817 - 4 2026-07-18
AAL1565 - 4 2026-07-15
AAL1312 - 4 2026-07-16
AAL1276 American Airlines 4 2026-06-07
AAL777 American Airlines 3 2026-07-07
AAL727 American Airlines 3 2026-05-23
AAL707 American Airlines 3 2026-06-04
AAL599 - 3 2026-07-14
AAL3320 American Airlines 3 2026-07-18
AAL3195 American Airlines 3 2026-05-16
AAL3137 American Airlines 3 2026-07-23
AAL2759 - 3 2026-06-26
AAL2670 - 3 2026-06-27
AAL2635 American Airlines 3 2026-05-14
AAL2612 - 3 2026-07-21

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 AAL3134 PVR → ORD Jul 26, 20:50 UTCJul 26, 22:10 UTC1h 20m
2026-07-26 AAL2041 CLT → MSP Jul 26, 17:00 UTCJul 26, 19:30 UTC2h 30m
2026-07-26 AAL1412 ONT → DFW Jul 26, 12:35 UTCJul 26, 14:15 UTC1h 40m
2026-07-26 AAL1412 ONT → DFW Jul 26, 12:31 UTCJul 26, 15:08 UTC2h 37m
2026-07-26 AAL3036 SDF → ORD Jul 26, 01:40 UTCJul 26, 05:50 UTC4h 10m
2026-07-25 AAL1919 PHL → MCO Jul 25, 22:00 UTCJul 26, 00:10 UTC2h 10m
2026-07-25 AAL1919 PHL → MCO Jul 25, 18:45 UTCJul 25, 20:45 UTC2h 0m
2026-07-25 AAL1274 MCO → AUS Jul 25, 13:50 UTCJul 25, 17:25 UTC3h 35m
2026-07-25 AAL2319 DFW → MSY Jul 25, 05:00 UTCJul 25, 06:50 UTC1h 50m
2026-07-25 AAL3286 PHX → DRO Jul 25, 01:00 UTCJul 25, 03:20 UTC2h 20m
2026-07-24 AAL750 CLT → LAS Jul 24, 18:55 UTCJul 24, 23:00 UTC4h 5m
2026-07-24 AAL1310 PUJ → AUS Jul 24, 13:10 UTCJul 24, 17:25 UTC4h 15m
2026-07-23 AAL3064 CLT → PDX Jul 23, 23:40 UTCJul 24, 04:40 UTC5h 0m
2026-07-23 AAL3064 CLT → PDX Jul 23, 23:35 UTCJul 24, 04:36 UTC5h 1m
2026-07-23 AAL611 FLL → PHL Jul 23, 17:39 UTCJul 23, 20:02 UTC2h 23m
2026-07-23 AAL611 FLL → PHL Jul 23, 13:45 UTCJul 23, 20:05 UTC6h 20m
2026-07-23 AAL2842 SFO → MIA Jul 23, 10:20 UTCJul 23, 11:40 UTC1h 20m
2026-07-23 AAL2842 SFO → MIA Jul 23, 10:17 UTCJul 23, 11:41 UTC1h 24m
2026-07-23 AAL3137 CLT → ORF Jul 23, 02:15 UTCJul 23, 05:15 UTC3h 0m
2026-07-22 AAL2986 SFO → CLT Jul 22, 22:40 UTCJul 23, 01:05 UTC2h 25m
2026-07-22 AAL2545 DFW → LGA Jul 22, 17:30 UTCJul 22, 21:23 UTC3h 53m
2026-07-22 AAL2545 DFW → LGA Jul 22, 17:35 UTCJul 22, 21:25 UTC3h 50m
2026-07-22 AAL1059 - Jul 22, 14:20 UTCJul 22, 16:05 UTC1h 45m
2026-07-22 AAL1059 DFW → ORD Jul 22, 14:15 UTCJul 22, 16:02 UTC1h 47m
2026-07-22 AAL1670 PHL → DFW Jul 22, 10:20 UTCJul 22, 12:25 UTC2h 5m
2026-07-21 AAL991 MIA → CNF Jul 21, 23:15 UTCJul 22, 02:15 UTC3h 0m
2026-07-21 AAL1828 - Jul 21, 18:20 UTCJul 21, 21:25 UTC3h 5m
2026-07-21 AAL1828 - Jul 21, 14:20 UTCJul 21, 16:55 UTC2h 35m
2026-07-21 AAL2612 DEN → DFW Jul 21, 11:10 UTCJul 21, 12:40 UTC1h 30m
2026-07-20 AAL2235 DFW → DEN Jul 20, 23:46 UTCJul 21, 01:12 UTC1h 26m
2026-07-20 AAL2235 DFW → DEN Jul 20, 23:50 UTCJul 21, 01:15 UTC1h 25m
2026-07-20 AAL767 SEA → DFW Jul 20, 18:55 UTCJul 20, 22:15 UTC3h 20m
2026-07-20 AAL767 - Jul 20, 13:45 UTCJul 20, 17:10 UTC3h 25m
2026-07-20 AAL2921 MIA → SAL Jul 20, 08:30 UTCJul 20, 10:45 UTC2h 15m
2026-07-20 AAL2998 CLE → DFW Jul 20, 04:45 UTCJul 20, 06:50 UTC2h 5m
2026-07-20 AAL2998 CLE → DFW Jul 20, 04:44 UTCJul 20, 06:48 UTC2h 4m
2026-07-19 AAL2947 PHL → DFW Jul 19, 23:00 UTCJul 20, 02:05 UTC3h 5m
2026-07-19 AAL2947 PHL → PHL Jul 19, 22:45 UTCJul 19, 22:50 UTC5m
2026-07-19 AAL2947 DFW → PHL Jul 19, 17:55 UTCJul 19, 21:00 UTC3h 5m
2026-07-19 AAL2075 MCO → DFW Jul 19, 13:55 UTCJul 19, 16:10 UTC2h 15m
2026-07-19 AAL1783 - Jul 19, 01:50 UTCJul 19, 02:55 UTC1h 5m
2026-07-18 AAL1192 - Jul 18, 21:15 UTCJul 18, 23:35 UTC2h 20m
2026-07-18 AAL1778 - Jul 18, 17:20 UTCJul 18, 19:55 UTC2h 35m
2026-07-18 AAL3320 PWM → PHL Jul 18, 14:30 UTCJul 18, 15:45 UTC1h 15m
2026-07-18 AAL3320 PWM → PHL Jul 18, 14:26 UTCJul 18, 15:40 UTC1h 14m
2026-07-18 AAL3320 PWM → PHL Jul 18, 12:00 UTCJul 18, 13:15 UTC1h 15m
2026-07-18 AAL1817 - Jul 18, 05:20 UTCJul 18, 09:50 UTC4h 30m
2026-07-17 AAL1817 - Jul 17, 23:10 UTCJul 18, 03:55 UTC4h 46m
2026-07-17 AAL2030 - Jul 17, 16:44 UTCJul 17, 20:44 UTC4h 0m
2026-07-17 AAL2030 - Jul 17, 11:35 UTCJul 17, 15:20 UTC3h 45m

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 N551UW page for operator, model, and routing details .

Mode-S A704F9 frequently asked

What is Mode-S code A704F9?
A704F9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N551UW.
Where is Mode-S A704F9 registered?
Mode-S code A704F9 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 A704F9 broadcasting right now?
Yes. Mode-S A704F9 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A704F9, octal 51602371, decimal 10,945,785.
What flights does A704F9 operate?
Mode-S A704F9 has broadcast 20 distinct callsigns, including AAL2947, AAL863, AAL402, AAL3064, AAL2762.