Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

A12B2F

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N17456 · operated by UNITED AIRLINES INC

Hex
A12B2F
Octal
50225457
Decimal
10,562,351
Country
US
Tail
N17456
No current signal · last broadcast 2d ago
Flights observed
150
Distinct callsigns
20
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A12B2F.

Country allocation

The ICAO 24-bit address A12B2F 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
UAL8133 - 4 2026-07-05
UAL2661 United Airlines 4 2026-06-30
UAL8102 - 3 2026-07-13
UAL3752 United Airlines 3 2026-07-23
UAL360 - 3 2026-07-14
UAL2632 United Airlines 3 2026-07-20
UAL2402 United Airlines 3 2026-07-26
UAL1609 - 3 2026-06-26
UAL1581 - 3 2026-07-19
UAL1103 United Airlines 3 2026-07-19
BOE956 - 3 2026-06-04
UAL583 - 2 2026-06-22
UAL413 - 2 2026-06-23
UAL3905 - 2 2026-06-19
UAL3778 United Airlines 2 2026-07-23
UAL3763 - 2 2026-06-25
UAL3739 - 2 2026-07-24
UAL3738 - 2 2026-07-24
UAL337 - 2 2026-06-29
UAL2740 - 2 2026-07-10

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 UAL1590 EWR → IAH Jul 26, 20:00 UTCJul 26, 21:45 UTC1h 45m
2026-07-26 UAL2402 LAX → BOS Jul 26, 15:05 UTCJul 26, 17:45 UTC2h 40m
2026-07-26 UAL2402 LAX → BOS Jul 26, 15:08 UTCJul 26, 18:09 UTC3h 1m
2026-07-26 UAL1823 SFO → DEN Jul 26, 12:10 UTCJul 26, 13:25 UTC1h 15m
2026-07-26 UAL497 CVG → DEN Jul 26, 01:35 UTCJul 26, 02:45 UTC1h 10m
2026-07-25 UAL2815 IAD → NRT Jul 25, 20:10 UTCJul 25, 23:10 UTC3h 0m
2026-07-25 UAL2402 LAX → BOS Jul 25, 15:20 UTCJul 25, 18:20 UTC3h 0m
2026-07-24 UAL3749 ADW → ORD Jul 24, 21:30 UTCJul 24, 23:20 UTC1h 50m
2026-07-24 UAL3739 - Jul 24, 19:40 UTCJul 24, 20:40 UTC1h 0m
2026-07-24 UAL3739 NBW → JAX Jul 24, 18:15 UTCJul 24, 20:35 UTC2h 20m
2026-07-24 UAL3738 - Jul 24, 14:25 UTCJul 24, 15:10 UTC45m
2026-07-24 UAL3738 NIP → NBW Jul 24, 13:43 UTCJul 24, 16:14 UTC2h 31m
2026-07-24 UAL3748 - Jul 24, 10:25 UTCJul 24, 12:15 UTC1h 50m
2026-07-24 UAL3755 LGA → IAD Jul 24, 01:20 UTCJul 24, 02:55 UTC1h 35m
2026-07-23 UAL3778 CLE → BOS Jul 23, 22:30 UTCJul 24, 00:30 UTC2h 0m
2026-07-23 UAL3752 CLE → ORD Jul 23, 16:25 UTCJul 23, 18:45 UTC2h 20m
2026-07-23 UAL2491 - Jul 23, 11:50 UTCJul 23, 13:25 UTC1h 35m
2026-07-22 UAL2818 PDX → SFO Jul 22, 18:05 UTCJul 22, 23:05 UTC5h 0m
2026-07-22 UAL2192 PHL → ORD Jul 22, 11:10 UTCJul 22, 16:05 UTC4h 55m
2026-07-22 UAL1646 SFO → AUS Jul 22, 00:45 UTCJul 22, 03:35 UTC2h 50m
2026-07-21 UAL2338 PSP → SFO Jul 21, 20:45 UTCJul 21, 22:40 UTC1h 55m
2026-07-21 UAL2368 SFO → DEN Jul 21, 17:15 UTCJul 21, 18:55 UTC1h 40m
2026-07-21 UAL595 AUS → DEN Jul 21, 13:40 UTCJul 21, 15:20 UTC1h 40m
2026-07-21 UAL312T ORD → CHS Jul 21, 01:35 UTCJul 21, 03:40 UTC2h 5m
2026-07-20 UAL1650 AUA → ORD Jul 20, 18:05 UTCJul 20, 23:00 UTC4h 55m
2026-07-20 UAL1203 - Jul 20, 16:05 UTCJul 20, 16:25 UTC20m
2026-07-20 UAL1203 IAD → STI Jul 20, 12:30 UTCJul 20, 15:25 UTC2h 55m
2026-07-20 UAL2632 MSY → EWR Jul 20, 04:37 UTCJul 20, 09:22 UTC4h 45m
2026-07-20 UAL2632 MSY → EWR Jul 20, 04:40 UTCJul 20, 09:15 UTC4h 35m
2026-07-19 UAL1103 DEN → BOS Jul 19, 21:20 UTCJul 20, 02:30 UTC5h 10m
2026-07-19 UAL1581 - Jul 19, 19:25 UTCJul 19, 19:40 UTC15m
2026-07-19 UAL1581 - Jul 19, 14:35 UTCJul 19, 15:10 UTC35m
2026-07-19 UAL1947 LGA → IAH Jul 19, 06:20 UTCJul 19, 07:05 UTC45m
2026-07-19 UAL1947 LGA → IAH Jul 19, 02:28 UTCJul 19, 07:03 UTC4h 35m
2026-07-18 UAL1260 SNA → SFO Jul 18, 20:00 UTCJul 19, 00:50 UTC4h 50m
2026-07-18 UAL1668 - Jul 18, 14:15 UTCJul 18, 17:20 UTC3h 5m
2026-07-18 UAL1807 - Jul 18, 07:50 UTCJul 18, 10:55 UTC3h 5m
2026-07-18 UAL1807 SFO → AUS Jul 18, 07:38 UTCJul 18, 10:54 UTC3h 16m
2026-07-17 UAL2400 BOS → SFO Jul 17, 23:04 UTCJul 18, 05:18 UTC6h 14m
2026-07-17 UAL2400 BOS → SFO Jul 17, 23:20 UTCJul 18, 05:35 UTC6h 16m
2026-07-17 UAL2647 SFO → BOS Jul 17, 15:25 UTCJul 17, 20:40 UTC5h 15m
2026-07-17 UAL1724 KOA → SFO Jul 17, 09:03 UTCJul 17, 13:55 UTC4h 52m
2026-07-17 UAL1724 - Jul 17, 08:59 UTCJul 17, 09:15 UTC15m
2026-07-17 UAL1723 - Jul 17, 00:30 UTCJul 17, 01:09 UTC40m
2026-07-16 UAL1074 - Jul 16, 17:10 UTCJul 16, 22:40 UTC5h 30m
2026-07-16 UAL641 IAD → BOS Jul 16, 12:49 UTCJul 16, 14:00 UTC1h 10m
2026-07-16 UAL264 SEA → IAD Jul 16, 06:45 UTCJul 16, 11:15 UTC4h 30m
2026-07-15 UAL326 IAD → SEA Jul 15, 22:05 UTCJul 16, 03:05 UTC5h 0m
2026-07-15 UAL2435 - Jul 15, 17:15 UTCJul 15, 19:15 UTC2h 0m
2026-07-15 UAL1073 IAD → MIA Jul 15, 13:05 UTCJul 15, 15:20 UTC2h 15m

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 N17456 page for operator, model, and routing details .

Mode-S A12B2F frequently asked

What is Mode-S code A12B2F?
A12B2F is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N17456.
Where is Mode-S A12B2F registered?
Mode-S code A12B2F 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 A12B2F broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A12B2F, octal 50225457, decimal 10,562,351.
What flights does A12B2F operate?
Mode-S A12B2F has broadcast 20 distinct callsigns, including UAL8133, UAL2661, UAL8102, UAL3752, UAL360.