sensors Mode-S transponder

A57D42

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N453AA · AIRBUS A-321neo · operated by AMERICAN AIRLINES INC

Hex
A57D42
Octal
51276502
Decimal
10,845,506
Country
US
Tail
N453AA
Type
A21N
Broadcasting now · callsign AAL3239 · 36,000 ft
Flights observed
220
Distinct callsigns
20
Country
US
Last broadcast
3h ago

Current position

A57D42 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A57D42 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 AAL2994 RSW → ORD May 29, 22:15 UTCMay 30, 00:45 UTC2h 30m
2026-05-29 AAL2408 NAS → LGA May 29, 15:30 UTCMay 29, 20:45 UTC5h 15m
2026-05-29 AAL2129 MIA → PHL May 29, 11:05 UTCMay 29, 13:30 UTC2h 25m
2026-05-29 AAL1824 MSY → PHL May 29, 01:00 UTCMay 29, 03:25 UTC2h 25m
2026-05-28 AAL2767 DFW → SEA May 28, 20:45 UTCMay 28, 22:50 UTC2h 5m
2026-05-28 AAL377 MIA → PAP May 28, 14:05 UTCMay 28, 19:05 UTC5h 0m
2026-05-27 AAL567 PHX → BOS May 27, 22:30 UTCMay 28, 02:45 UTC4h 15m
2026-05-27 AAL2655 PDX → DFW May 27, 19:55 UTCMay 27, 20:50 UTC55m
2026-05-27 AAL2655 PDX → DFW May 27, 17:35 UTCMay 27, 18:35 UTC1h 0m
2026-05-27 AAL1061 DFW → JAX May 27, 11:25 UTCMay 27, 15:50 UTC4h 25m
2026-05-27 AAL2205 MIA → TQO May 27, 05:14 UTCMay 27, 09:20 UTC4h 5m
2026-05-27 AAL1362 BNA → ORD May 27, 02:38 UTCMay 27, 03:37 UTC59m
2026-05-26 AAL1451 DCA → PVD May 26, 20:00 UTCMay 27, 00:59 UTC5h 0m
2026-05-26 AAL1451 DCA → PVD May 26, 13:10 UTCMay 26, 17:55 UTC4h 45m
2026-05-26 AAL1504 LAX → ORD May 26, 04:30 UTCMay 26, 07:10 UTC2h 40m
2026-05-26 AAL1973 DFW → SFO May 26, 01:34 UTCMay 26, 02:29 UTC55m
2026-05-25 AAL1973 DFW → SFO May 25, 19:20 UTCMay 25, 22:34 UTC3h 15m
2026-05-25 AAL1973 DFW → SFO May 25, 14:30 UTCMay 25, 17:45 UTC3h 15m
2026-05-25 AAL3260 GJT → PHX May 25, 01:55 UTCMay 25, 03:55 UTC2h 0m
2026-05-24 AAL345 CLT → MSP May 24, 15:25 UTCMay 24, 20:00 UTC4h 35m
2026-05-24 AAL286 PHL → STL May 24, 08:10 UTCMay 24, 13:10 UTC5h 0m
2026-05-24 AAL286 PHL → STL May 24, 07:59 UTCMay 24, 13:10 UTC5h 11m
2026-05-24 AAL510 PHL → SAN May 24, 01:01 UTCMay 24, 06:12 UTC5h 11m
2026-05-24 AAL510 PHL → SAN May 24, 01:05 UTCMay 24, 06:05 UTC5h 0m
2026-05-23 AAL2368 BWI → DFW May 23, 21:35 UTCMay 23, 22:30 UTC55m
2026-05-23 AAL646 PHL → MCO May 23, 15:05 UTCMay 23, 19:35 UTC4h 30m
2026-05-23 AAL646 PHL → MCO May 23, 15:04 UTCMay 23, 19:35 UTC4h 31m
2026-05-23 AAL2764 PHL → BOS May 23, 12:20 UTCMay 23, 13:25 UTC1h 5m
2026-05-22 AAL366 RDU → LGA May 22, 20:35 UTCMay 23, 00:50 UTC4h 15m
2026-05-22 AAL366 RDU → LGA May 22, 20:35 UTCMay 23, 00:48 UTC4h 13m
2026-05-22 AAL2820 DFW → SFO May 22, 14:10 UTCMay 22, 18:40 UTC4h 30m
2026-05-22 AAL2758 SAN → PHL May 22, 07:05 UTCMay 22, 11:45 UTC4h 40m
2026-05-22 AAL2758 SAN → PHL May 22, 07:04 UTCMay 22, 11:44 UTC4h 40m
2026-05-22 AAL164 SFO → JFK May 22, 04:45 UTCMay 22, 05:30 UTC45m
2026-05-22 AAL164 SFO → JFK May 22, 00:15 UTCMay 22, 00:30 UTC15m
2026-05-21 AAL693 PHL → CLT May 21, 21:30 UTCMay 21, 21:50 UTC20m
2026-05-21 AAL693 PHL → CLT May 21, 15:55 UTCMay 21, 17:25 UTC1h 30m
2026-05-21 AAL693 PHL → CLT May 21, 15:53 UTCMay 21, 21:48 UTC5h 55m
2026-05-21 AAL684 PHX → LIH May 21, 07:45 UTCMay 21, 13:05 UTC5h 20m
2026-05-20 AAL697 LIH → PHX May 20, 19:35 UTCMay 21, 01:40 UTC6h 5m
2026-05-20 AAL2820 DFW → SFO May 20, 13:00 UTCMay 20, 17:40 UTC4h 40m
2026-05-20 AAL1713 CLT → PHL May 20, 06:25 UTCMay 20, 10:50 UTC4h 25m
2026-05-19 AAL1451 DCA → PVD May 19, 22:20 UTCMay 20, 04:15 UTC5h 55m
2026-05-19 AAL3172 YUM → PHX May 19, 15:20 UTCMay 19, 19:55 UTC4h 35m
2026-05-19 AAL14 OGG → LAX May 19, 11:55 UTCMay 19, 12:25 UTC30m
2026-05-18 AAL645 DFW → EWR May 18, 18:10 UTCMay 18, 19:30 UTC1h 19m
2026-05-18 AAL2721 MCO → ORD May 18, 04:40 UTCMay 18, 05:35 UTC55m
2026-05-18 AAL2721 MCO → ORD May 18, 02:40 UTCMay 18, 03:30 UTC50m
2026-05-17 AAL1454 BTV → PHL May 17, 19:45 UTCMay 18, 00:10 UTC4h 25m
2026-05-17 AAL1454 BTV → PHL May 17, 19:44 UTCMay 18, 00:10 UTC4h 26m

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 N453AA page for operator, model, and routing details .

Mode-S A57D42 frequently asked

What is Mode-S code A57D42?
A57D42 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N453AA.
Where is Mode-S A57D42 registered?
Mode-S code A57D42 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 A57D42 broadcasting right now?
Yes. Mode-S A57D42 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A57D42, octal 51276502, decimal 10,845,506.
What flights does A57D42 operate?
Mode-S A57D42 has broadcast 20 distinct callsigns, including AAL693, AAL767, AAL988, AAL3220, AAL3202.