sensors Mode-S transponder

A12B2D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N17454 · operated by UNITED AIRLINES INC

Hex
A12B2D
Octal
50225455
Decimal
10,562,349
Country
US
Tail
N17454
No current signal · last broadcast 3h ago
Flights observed
286
Distinct callsigns
20
Country
US
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S A12B2D.

Country allocation

The ICAO 24-bit address A12B2D 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
UAL650 United Airlines 7 2026-07-19
UAL2380 United Airlines 7 2026-07-18
UAL1804 - 5 2026-07-15
UAL1581 - 5 2026-06-27
UAL668 - 4 2026-07-14
UAL569 - 4 2026-07-12
UAL2040 - 4 2026-07-06
UAL1572 - 4 2026-06-27
UAL1556 United Airlines 4 2026-06-09
UAL1162 - 4 2026-07-13
UAL788 - 3 2026-07-04
UAL3820 United Airlines 3 2026-05-16
UAL2857 - 3 2026-06-15
UAL1947 - 3 2026-06-27
UAL1650 United Airlines 3 2026-06-07
UAL1644 United Airlines 3 2026-05-19
UAL1139 - 3 2026-07-03
BOE954 - 3 2026-04-23
UAL8227 United Airlines 2 2026-06-25
UAL774 United Airlines 2 2026-05-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-21 UAL1192 IAH → SJU Jul 21, 19:15 UTCJul 21, 19:40 UTC25m
2026-07-21 UAL1192 IAH → SJU Jul 21, 15:25 UTCJul 21, 17:45 UTC2h 20m
2026-07-21 UAL537 - Jul 21, 12:10 UTCJul 21, 13:20 UTC1h 10m
2026-07-21 UAL1794 OGG → SFO Jul 21, 01:45 UTCJul 21, 02:45 UTC1h 0m
2026-07-20 UAL1183 - Jul 20, 20:15 UTCJul 20, 23:40 UTC3h 25m
2026-07-20 UAL2393 - Jul 20, 15:15 UTCJul 20, 18:50 UTC3h 35m
2026-07-20 UAL2393 IAH → BOS Jul 20, 15:10 UTCJul 20, 18:49 UTC3h 39m
2026-07-20 UAL468 SFO → LAS Jul 20, 11:20 UTCJul 20, 13:25 UTC2h 5m
2026-07-19 UAL520 - Jul 19, 22:30 UTCJul 20, 03:20 UTC4h 50m
2026-07-19 UAL2017 MCO → SFO Jul 19, 15:35 UTCJul 19, 20:30 UTC4h 55m
2026-07-19 UAL1267 SFO → MCO Jul 19, 08:35 UTCJul 19, 13:35 UTC5h 0m
2026-07-19 UAL650 CLT → EWR Jul 19, 05:55 UTCJul 19, 06:35 UTC40m
2026-07-19 UAL650 CLT → EWR Jul 19, 02:10 UTCJul 19, 02:30 UTC20m
2026-07-18 UAL2380 SFO → HNL Jul 18, 23:45 UTCJul 19, 00:05 UTC20m
2026-07-18 UAL2380 SFO → HNL Jul 18, 19:05 UTCJul 18, 19:35 UTC30m
2026-07-18 UAL1768 EWR → DEN Jul 18, 13:35 UTCJul 18, 17:00 UTC3h 25m
2026-07-18 UAL505 - Jul 18, 07:45 UTCJul 18, 11:05 UTC3h 20m
2026-07-18 UAL650 CLT → EWR Jul 18, 01:00 UTCJul 18, 01:15 UTC15m
2026-07-18 UAL650 CLT → EWR Jul 18, 00:59 UTCJul 18, 05:36 UTC4h 37m
2026-07-17 UAL2380 - Jul 17, 23:10 UTCJul 17, 23:25 UTC15m
2026-07-17 UAL2380 - Jul 17, 18:25 UTCJul 17, 19:05 UTC40m
2026-07-17 UAL2177 - Jul 17, 11:04 UTCJul 17, 15:40 UTC4h 35m
2026-07-17 UAL2117 - Jul 17, 04:54 UTCJul 17, 09:20 UTC4h 25m
2026-07-16 UAL512 SAN → SFO Jul 16, 20:49 UTCJul 17, 02:34 UTC5h 45m
2026-07-16 UAL1392 IAD → BOS Jul 16, 17:20 UTCJul 16, 18:50 UTC1h 30m
2026-07-16 UAL276 MCO → IAD Jul 16, 13:00 UTCJul 16, 14:45 UTC1h 45m
2026-07-16 UAL276 MCO → IAD Jul 16, 13:10 UTCJul 16, 14:44 UTC1h 34m
2026-07-16 UAL689 IAD → MCO Jul 16, 02:50 UTCJul 16, 04:35 UTC1h 45m
2026-07-15 UAL1648 - Jul 15, 20:50 UTCJul 16, 00:50 UTC4h 0m
2026-07-15 UAL1804 - Jul 15, 19:10 UTCJul 15, 19:30 UTC20m
2026-07-15 UAL1804 - Jul 15, 15:25 UTCJul 15, 17:20 UTC1h 55m
2026-07-15 UAL1804 IAH → AUA Jul 15, 15:00 UTCJul 15, 19:24 UTC4h 24m
2026-07-15 UAL2358 - Jul 15, 11:35 UTCJul 15, 13:30 UTC1h 55m
2026-07-15 UAL465 - Jul 15, 01:15 UTCJul 15, 03:05 UTC1h 50m
2026-07-14 UAL668 - Jul 14, 14:00 UTCJul 14, 23:30 UTC9h 29m
2026-07-14 UAL1833 BOS → EWR Jul 14, 10:35 UTCJul 14, 11:20 UTC45m
2026-07-14 UAL521 - Jul 14, 02:30 UTCJul 14, 05:55 UTC3h 25m
2026-07-13 UAL2492 - Jul 13, 21:10 UTCJul 13, 23:45 UTC2h 35m
2026-07-13 UAL2492 LAS → IAH Jul 13, 20:21 UTCJul 13, 23:44 UTC3h 23m
2026-07-13 UAL723 - Jul 13, 14:30 UTCJul 13, 17:35 UTC3h 5m
2026-07-13 UAL723 ORD → LAS Jul 13, 14:37 UTCJul 13, 17:33 UTC2h 56m
2026-07-13 UAL530 EWR → ORD Jul 13, 10:27 UTCJul 13, 12:00 UTC1h 33m
2026-07-13 UAL530 - Jul 13, 10:25 UTCJul 13, 12:25 UTC2h 0m
2026-07-13 UAL1162 - Jul 13, 06:45 UTCJul 13, 07:45 UTC1h 0m
2026-07-13 UAL1162 BQN → EWR Jul 13, 04:32 UTCJul 13, 07:41 UTC3h 9m
2026-07-12 UAL569 EWR → BQN Jul 12, 23:36 UTCJul 13, 02:34 UTC2h 58m
2026-07-12 UAL569 - Jul 12, 23:15 UTCJul 12, 23:20 UTC5m
2026-07-12 UAL681 NAS → EWR Jul 12, 18:52 UTCJul 12, 21:11 UTC2h 19m
2026-07-12 UAL1480 - Jul 12, 14:35 UTCJul 12, 19:15 UTC4h 40m
2026-07-12 UAL2158 - Jul 12, 10:05 UTCJul 12, 12:15 UTC2h 10m

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 N17454 page for operator, model, and routing details .

Mode-S A12B2D frequently asked

What is Mode-S code A12B2D?
A12B2D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N17454.
Where is Mode-S A12B2D registered?
Mode-S code A12B2D 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 A12B2D broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A12B2D, octal 50225455, decimal 10,562,349.
What flights does A12B2D operate?
Mode-S A12B2D has broadcast 20 distinct callsigns, including UAL650, UAL2380, UAL1804, UAL1581, UAL668.