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sensors Mode-S transponder

A55F31

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N445WN · BOEING 737-700 · operated by SOUTHWEST AIRLINES CO

Hex
A55F31
Octal
51257461
Decimal
10,837,809
Country
US
Tail
N445WN
Type
B737
Broadcasting now · callsign SWA406 · 7,325 ft
Flights observed
694
Distinct callsigns
20
Country
US
Last broadcast
7h ago

Current position

A55F31 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A55F31 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
SWA1723 - 7 2026-06-17
SWA670 - 5 2026-07-14
SWA1416 - 5 2026-07-11
SWA893 - 4 2026-07-12
SWA4155 Southwest Airlines 4 2026-05-10
SWA3968 Southwest Airlines 4 2026-05-25
SWA345 Southwest Airlines 4 2026-06-06
SWA3078 Southwest Airlines 4 2026-05-18
SWA30 Southwest Airlines 4 2026-04-27
SWA295 Southwest Airlines 4 2026-06-05
SWA2665 Southwest Airlines 4 2026-04-17
SWA2560 Southwest Airlines 4 2026-04-26
SWA2409 Southwest Airlines 4 2026-06-03
SWA2278 Southwest Airlines 4 2026-05-26
SWA1887 Southwest Airlines 4 2026-04-14
SWA1776 Southwest Airlines 4 2026-05-05
SWA1655 Southwest Airlines 4 2026-04-21
SWA1505 Southwest Airlines 4 2026-05-11
SWA1317 Southwest Airlines 4 2026-04-17
SWA1015 - 4 2026-06-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SWA4303 DEN → SFO Jul 14, 05:05 UTCJul 14, 07:10 UTC2h 5m
2026-07-14 SWA4303 DEN → SFO Jul 14, 05:01 UTCJul 14, 07:07 UTC2h 6m
2026-07-14 SWA670 SMF → DEN Jul 14, 00:50 UTCJul 14, 02:50 UTC2h 0m
2026-07-13 SWA670 - Jul 13, 23:05 UTCJul 14, 00:00 UTC55m
2026-07-13 SWA670 PHX → ONT Jul 13, 21:25 UTCJul 13, 22:10 UTC45m
2026-07-13 SWA670 - Jul 13, 17:15 UTCJul 13, 20:15 UTC3h 0m
2026-07-13 SWA670 BNA → SDF Jul 13, 15:45 UTCJul 13, 16:15 UTC30m
2026-07-13 SWA1785 - Jul 13, 13:05 UTCJul 13, 14:10 UTC1h 5m
2026-07-13 SWA2712 - Jul 13, 04:10 UTCJul 13, 05:31 UTC1h 20m
2026-07-13 SWA2712 STL → ECP Jul 13, 04:06 UTCJul 13, 05:31 UTC1h 25m
2026-07-13 SWA2712 DCA → STL Jul 13, 01:45 UTCJul 13, 03:30 UTC1h 45m
2026-07-12 SWA686 ATL → DCA Jul 12, 23:30 UTCJul 13, 00:50 UTC1h 20m
2026-07-12 SWA893 - Jul 12, 20:10 UTCJul 12, 20:55 UTC45m
2026-07-12 SWA893 BNA → ATL Jul 12, 20:09 UTCJul 12, 20:54 UTC45m
2026-07-12 SWA893 - Jul 12, 16:50 UTCJul 12, 17:55 UTC1h 5m
2026-07-12 SWA893 - Jul 12, 15:01 UTCJul 12, 15:50 UTC50m
2026-07-12 SWA4064 SAV → BWI Jul 12, 12:05 UTCJul 12, 13:35 UTC1h 30m
2026-07-11 SWA3138 - Jul 11, 23:00 UTCJul 12, 00:40 UTC1h 40m
2026-07-11 SWA1539 GRR → MDW Jul 11, 21:35 UTCJul 11, 22:10 UTC35m
2026-07-11 SWA1539 - Jul 11, 19:10 UTCJul 11, 20:30 UTC1h 20m
2026-07-11 SWA1211 - Jul 11, 16:55 UTCJul 11, 18:00 UTC1h 5m
2026-07-11 SWA1211 - Jul 11, 14:15 UTCJul 11, 15:55 UTC1h 40m
2026-07-11 SWA3386 - Jul 11, 11:20 UTCJul 11, 13:15 UTC1h 55m
2026-07-11 SWA3386 PIT → STL Jul 11, 11:16 UTCJul 11, 13:08 UTC1h 53m
2026-07-11 SWA1416 - Jul 11, 03:05 UTCJul 11, 05:01 UTC1h 55m
2026-07-11 SWA1416 - Jul 11, 01:10 UTCJul 11, 01:55 UTC45m
2026-07-10 SWA1416 - Jul 10, 21:30 UTCJul 11, 00:15 UTC2h 45m
2026-07-10 SWA2116 - Jul 10, 18:30 UTCJul 10, 20:15 UTC1h 45m
2026-07-10 SWA2116 - Jul 10, 16:10 UTCJul 10, 17:25 UTC1h 15m
2026-07-10 SWA2116 AUS → MCO Jul 10, 12:50 UTCJul 10, 15:05 UTC2h 15m
2026-07-10 SWA3998 TPA → AUS Jul 10, 09:45 UTCJul 10, 11:45 UTC2h 0m
2026-07-10 SWA9004 - Jul 10, 00:55 UTCJul 10, 02:50 UTC1h 55m
2026-07-10 SWA9004 DAL → TPA Jul 10, 00:53 UTCJul 10, 02:48 UTC1h 55m
2026-07-09 SWA9004 - Jul 9, 22:45 UTCJul 9, 23:55 UTC1h 10m
2026-07-09 SWA2804 - Jul 9, 20:25 UTCJul 9, 21:10 UTC45m
2026-07-09 SWA3409 - Jul 9, 17:05 UTCJul 9, 19:15 UTC2h 10m
2026-07-09 SWA3409 PVD → MDW Jul 9, 17:04 UTCJul 9, 19:09 UTC2h 5m
2026-07-09 SWA4628 BWI → PVD Jul 9, 14:55 UTCJul 9, 16:04 UTC1h 9m
2026-07-09 SWA1899 - Jul 9, 12:40 UTCJul 9, 13:55 UTC1h 15m
2026-07-08 SWA3839 - Jul 8, 23:00 UTCJul 9, 00:00 UTC1h 0m
2026-07-08 SWA3196 - Jul 8, 20:30 UTCJul 8, 21:35 UTC1h 5m
2026-07-08 SWA1062 - Jul 8, 18:40 UTCJul 8, 19:30 UTC50m
2026-07-08 SWA2143 - Jul 8, 16:45 UTCJul 8, 17:40 UTC55m
2026-07-08 SWA2143 ISP → BWI Jul 8, 16:44 UTCJul 8, 17:37 UTC53m
2026-07-08 SWA4691 - Jul 8, 14:55 UTCJul 8, 15:40 UTC45m
2026-07-08 SWA1077 - Jul 8, 12:40 UTCJul 8, 14:00 UTC1h 20m
2026-07-08 SWA1077 TYS → BWI Jul 8, 12:38 UTCJul 8, 13:54 UTC1h 16m
2026-07-08 SWA443 - Jul 8, 00:40 UTCJul 8, 01:50 UTC1h 10m
2026-07-07 SWA554 - Jul 7, 21:35 UTCJul 7, 23:00 UTC1h 25m
2026-07-07 SWA554 - Jul 7, 18:20 UTCJul 7, 20:20 UTC2h 0m

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 N445WN page for operator, model, and routing details .

Mode-S A55F31 frequently asked

What is Mode-S code A55F31?
A55F31 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N445WN.
Where is Mode-S A55F31 registered?
Mode-S code A55F31 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 A55F31 broadcasting right now?
Yes. Mode-S A55F31 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A55F31, octal 51257461, decimal 10,837,809.
What flights does A55F31 operate?
Mode-S A55F31 has broadcast 20 distinct callsigns, including SWA1723, SWA670, SWA1416, SWA893, SWA4155.