sensors Mode-S transponder

AAA125

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N784UA · BOEING 777-200 · operated by UNITED AIRLINES INC

Hex
AAA125
Octal
52520445
Decimal
11,182,373
Country
US
Tail
N784UA
Type
B772
No current signal · last broadcast 4h ago
Flights observed
134
Distinct callsigns
20
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S AAA125.

Country allocation

The ICAO 24-bit address AAA125 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
UAL919 United Airlines 7 2026-05-10
UAL918 United Airlines 7 2026-05-05
UAL943 - 6 2026-07-09
UAL942 - 6 2026-07-09
UAL925 - 6 2026-07-08
UAL149 - 6 2026-07-01
UAL914 United Airlines 5 2026-05-16
UAL819 - 5 2026-06-20
UAL818 - 5 2026-06-21
UAL915 - 4 2026-07-10
UAL880 United Airlines 4 2026-06-22
UAL879 - 4 2026-06-23
UAL160 - 4 2026-07-04
UAL148 - 4 2026-07-02
UAL984 - 3 2026-07-13
UAL57 - 3 2026-07-12
UAL195 United Airlines 3 2026-06-24
UAL194 - 3 2026-07-03
UAL990 - 2 2026-07-13
UAL932 - 2 2026-06-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 UAL990 - Jul 13, 22:20 UTCJul 14, 00:35 UTC2h 15m
2026-07-13 UAL984 - Jul 13, 07:45 UTCJul 13, 18:35 UTC10h 50m
2026-07-13 UAL984 CDG → SFO Jul 13, 07:39 UTCJul 13, 18:23 UTC10h 44m
2026-07-12 UAL57 EWR → CDG Jul 12, 22:13 UTCJul 13, 04:30 UTC6h 17m
2026-07-12 UAL57 EWR → CDG Jul 12, 22:00 UTCJul 13, 04:35 UTC6h 35m
2026-07-12 UAL18 MXP → EWR Jul 12, 08:40 UTCJul 12, 16:35 UTC7h 55m
2026-07-11 UAL19 EWR → MXP Jul 11, 22:08 UTCJul 12, 05:08 UTC7h 0m
2026-07-11 UAL19 EWR → MXP Jul 11, 22:05 UTCJul 12, 05:10 UTC7h 5m
2026-07-11 UAL56 - Jul 11, 08:05 UTCJul 11, 15:50 UTC7h 45m
2026-07-11 UAL56 CDG → EWR Jul 11, 08:09 UTCJul 11, 15:46 UTC7h 37m
2026-07-10 UAL915 IAD → CDG Jul 10, 22:46 UTCJul 11, 05:26 UTC6h 40m
2026-07-10 UAL915 IAD → CDG Jul 10, 22:45 UTCJul 11, 05:31 UTC6h 45m
2026-07-10 UAL885 - Jul 10, 09:25 UTCJul 10, 18:50 UTC9h 25m
2026-07-09 UAL884 IAD → FCO Jul 9, 22:35 UTCJul 10, 07:00 UTC8h 25m
2026-07-09 UAL943 LIS → IAD Jul 9, 11:25 UTCJul 9, 19:10 UTC7h 45m
2026-07-09 UAL942 IAD → LIS Jul 9, 03:05 UTCJul 9, 09:30 UTC6h 25m
2026-07-08 UAL925 - Jul 8, 15:55 UTCJul 8, 17:10 UTC1h 15m
2026-07-08 UAL925 LHR → IAD Jul 8, 16:04 UTCJul 8, 23:14 UTC7h 10m
2026-07-08 UAL5 - Jul 8, 03:00 UTCJul 8, 11:40 UTC8h 40m
2026-07-07 UAL4 - Jul 7, 13:00 UTCJul 7, 23:10 UTC10h 10m
2026-07-07 UAL5 - Jul 7, 01:35 UTCJul 7, 10:40 UTC9h 5m
2026-07-05 UAL47 - Jul 5, 12:10 UTCJul 5, 22:45 UTC10h 35m
2026-07-05 UAL46 - Jul 5, 00:20 UTCJul 5, 09:25 UTC9h 5m
2026-07-04 UAL160 - Jul 4, 10:55 UTCJul 4, 21:50 UTC10h 55m
2026-07-03 UAL194 - Jul 3, 22:00 UTCJul 4, 08:20 UTC10h 20m
2026-07-03 UAL984 - Jul 3, 07:25 UTCJul 3, 18:15 UTC10h 50m
2026-07-02 UAL57 EWR → CDG Jul 2, 22:40 UTCJul 3, 05:05 UTC6h 25m
2026-07-02 UAL148 - Jul 2, 00:25 UTCJul 2, 01:05 UTC40m
2026-07-02 UAL148 GRU → EWR Jul 2, 00:21 UTCJul 2, 09:31 UTC9h 10m
2026-07-01 UAL149 EWR → GRU Jul 1, 01:01 UTCJul 1, 09:53 UTC8h 52m
2026-07-01 UAL149 - Jul 1, 01:10 UTCJul 1, 09:55 UTC8h 45m
2026-06-30 UAL55 - Jun 30, 11:45 UTCJun 30, 19:05 UTC7h 20m
2026-06-30 UAL54 EWR → CDG Jun 30, 02:04 UTCJun 30, 08:36 UTC6h 32m
2026-06-30 UAL54 - Jun 30, 02:05 UTCJun 30, 08:35 UTC6h 30m
2026-06-29 UAL130 HND → EWR Jun 29, 09:45 UTCJun 29, 22:00 UTC12h 15m
2026-06-29 UAL130 HND → EWR Jun 29, 10:00 UTCJun 29, 22:05 UTC12h 5m
2026-06-28 UAL803 IAD → HND Jun 28, 17:55 UTCJun 29, 07:30 UTC13h 35m
2026-06-27 UAL925 - Jun 27, 16:20 UTCJun 27, 17:25 UTC1h 5m
2026-06-27 UAL925 LHR → IAD Jun 27, 16:19 UTCJun 27, 23:19 UTC7h 0m
2026-06-27 UAL924 IAD → LHR Jun 27, 02:50 UTCJun 27, 09:55 UTC7h 5m
2026-06-26 UAL925 - Jun 26, 16:09 UTCJun 26, 23:34 UTC7h 25m
2026-06-26 UAL924 IAD → LHR Jun 26, 03:39 UTCJun 26, 10:05 UTC6h 25m
2026-06-25 UAL925 - Jun 25, 16:05 UTCJun 25, 23:39 UTC7h 35m
2026-06-25 UAL948 - Jun 25, 00:40 UTCJun 25, 10:30 UTC9h 50m
2026-06-24 UAL195 MUC → SFO Jun 24, 10:04 UTCJun 24, 21:19 UTC11h 15m
2026-06-24 UAL195 MUC → SFO Jun 24, 10:02 UTCJun 24, 21:14 UTC11h 12m
2026-06-23 UAL102 - Jun 23, 22:15 UTCJun 24, 07:40 UTC9h 25m
2026-06-23 UAL879 - Jun 23, 09:40 UTCJun 23, 19:10 UTC9h 30m
2026-06-22 UAL880 IAH → LHR Jun 22, 22:30 UTCJun 23, 07:15 UTC8h 45m
2026-06-22 UAL879 - Jun 22, 10:05 UTCJun 22, 19:40 UTC9h 35m

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 N784UA page for operator, model, and routing details .

Mode-S AAA125 frequently asked

What is Mode-S code AAA125?
AAA125 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N784UA.
Where is Mode-S AAA125 registered?
Mode-S code AAA125 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 AAA125 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AAA125, octal 52520445, decimal 11,182,373.
What flights does AAA125 operate?
Mode-S AAA125 has broadcast 20 distinct callsigns, including UAL919, UAL918, UAL943, UAL942, UAL925.