sensors Mode-S transponder

AC20C4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N8804L · BOEING 737 MAX 8 · operated by SOUTHWEST AIRLINES CO

Hex
AC20C4
Octal
53020304
Decimal
11,280,580
Country
US
Tail
N8804L
Type
B38M
No current signal · last broadcast 4h ago
Flights observed
341
Distinct callsigns
20
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S AC20C4.

Country allocation

The ICAO 24-bit address AC20C4 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
2026-05-30 SWA2326 PDX → SJC May 30, 02:35 UTCMay 30, 04:40 UTC2h 5m
2026-05-30 SWA2326 PDX → SJC May 30, 02:32 UTCMay 30, 04:37 UTC2h 5m
2026-05-29 SWA2198 IND → DEN May 29, 23:55 UTCMay 30, 01:25 UTC1h 30m
2026-05-29 SWA3630 DEN → PHL May 29, 21:15 UTCMay 29, 22:30 UTC1h 15m
2026-05-29 SWA3630 DEN → PHL May 29, 17:55 UTCMay 29, 20:00 UTC2h 5m
2026-05-29 SWA3285 LAS → LBB May 29, 13:10 UTCMay 29, 16:20 UTC3h 10m
2026-05-29 SWA3465 CVG → BWI May 29, 10:30 UTCMay 29, 11:30 UTC1h 0m
2026-05-29 SWA3465 CVG → BWI May 29, 10:27 UTCMay 29, 11:27 UTC1h 0m
2026-05-29 SWA3425 SJC → LAX May 29, 03:55 UTCMay 29, 05:30 UTC1h 35m
2026-05-28 SWA519 STL → LGA May 28, 23:50 UTCMay 29, 02:40 UTC2h 50m
2026-05-28 SWA519 STL → LGA May 28, 23:45 UTCMay 29, 02:35 UTC2h 50m
2026-05-28 SWA3345 MHT → MDW May 28, 19:25 UTCMay 28, 22:30 UTC3h 5m
2026-05-28 SWA3345 MHT → MDW May 28, 19:20 UTCMay 28, 22:27 UTC3h 7m
2026-05-28 SWA3292 RDU → BWI May 28, 14:34 UTCMay 28, 17:59 UTC3h 26m
2026-05-28 SWA3292 RDU → BWI May 28, 14:35 UTCMay 28, 18:00 UTC3h 25m
2026-05-28 SWA1772 SMF → PDX May 28, 02:15 UTCMay 28, 03:25 UTC1h 10m
2026-05-27 SWA4132 OAK → AUS May 27, 23:40 UTCMay 28, 00:50 UTC1h 10m
2026-05-27 SWA4132 OAK → AUS May 27, 23:37 UTCMay 28, 00:45 UTC1h 8m
2026-05-27 SWA4371 MHT → BWI May 27, 21:25 UTCMay 27, 22:35 UTC1h 10m
2026-05-27 SWA2792 RSW → MKE May 27, 19:10 UTCMay 27, 20:20 UTC1h 10m
2026-05-27 SWA2650 OAK → LAS May 27, 16:00 UTCMay 27, 18:00 UTC2h 0m
2026-05-27 SWA4194 SAN → DEN May 27, 13:00 UTCMay 27, 14:25 UTC1h 25m
2026-05-27 SWA3417 LAS → OAK May 27, 02:49 UTCMay 27, 06:29 UTC3h 40m
2026-05-27 SWA3417 LAS → OAK May 27, 02:48 UTCMay 27, 06:28 UTC3h 40m
2026-05-26 SWA1956 BUR → SJC May 26, 20:54 UTCMay 26, 22:20 UTC1h 25m
2026-05-26 SWA3782 ATL → MSY May 26, 18:16 UTCMay 26, 19:41 UTC1h 26m
2026-05-26 SWA3782 ATL → MSY May 26, 18:19 UTCMay 26, 19:40 UTC1h 20m
2026-05-26 SWA1373 OAK → LGB May 26, 15:29 UTCMay 26, 16:55 UTC1h 25m
2026-05-26 SWA1428 SJC → SAN May 26, 13:19 UTCMay 26, 14:24 UTC1h 5m
2026-05-26 SWA4316 BWI → SAN May 26, 03:55 UTCMay 26, 04:54 UTC1h 0m
2026-05-26 SWA4316 BWI → SAN May 26, 03:54 UTCMay 26, 04:54 UTC1h 0m
2026-05-26 SWA3962 ONT → SJC May 26, 01:34 UTCMay 26, 02:44 UTC1h 10m
2026-05-25 SWA4262 BOI → PHX May 25, 23:40 UTCMay 26, 00:29 UTC50m
2026-05-25 SWA3882 OAK → SAN May 25, 21:19 UTCMay 25, 22:49 UTC1h 30m
2026-05-25 SWA3882 OAK → SAN May 25, 21:17 UTCMay 25, 22:45 UTC1h 28m
2026-05-25 SWA1066 STL → TPA May 25, 17:25 UTCMay 25, 19:54 UTC2h 29m
2026-05-25 SWA1066 STL → TPA May 25, 17:21 UTCMay 25, 19:50 UTC2h 29m
2026-05-25 SWA3080 LAS → SJC May 25, 15:20 UTCMay 25, 16:10 UTC50m
2026-05-25 SWA3080 LAS → SJC May 25, 15:19 UTCMay 25, 16:08 UTC49m
2026-05-25 SWA3350 SJC → BUR May 25, 13:15 UTCMay 25, 14:20 UTC1h 5m
2026-05-25 SWA2673 OAK → GEG May 25, 10:55 UTCMay 25, 11:35 UTC40m
2026-05-25 SWA513 MCO → MDW May 25, 01:55 UTCMay 25, 02:30 UTC35m
2026-05-24 SWA3833 SAN → SFO May 24, 21:15 UTCMay 24, 23:30 UTC2h 15m
2026-05-24 SWA4248 BUF → MCO May 24, 19:15 UTCMay 24, 20:10 UTC55m
2026-05-24 SWA4248 BUF → MCO May 24, 19:11 UTCMay 24, 20:09 UTC58m
2026-05-24 SWA2449 SJC → SAN May 24, 17:15 UTCMay 24, 18:05 UTC50m
2026-05-24 SWA4020 FLL → BWI May 24, 15:25 UTCMay 24, 16:25 UTC1h 0m
2026-05-23 SWA1924 BUR → SJC May 23, 23:35 UTCMay 24, 02:40 UTC3h 5m
2026-05-23 SWA1924 BUR → SJC May 23, 21:45 UTCMay 23, 22:30 UTC45m
2026-05-23 SWA1924 BUR → SJC May 23, 19:00 UTCMay 23, 20:25 UTC1h 25m

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 N8804L page for operator, model, and routing details .

Mode-S AC20C4 frequently asked

What is Mode-S code AC20C4?
AC20C4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N8804L.
Where is Mode-S AC20C4 registered?
Mode-S code AC20C4 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 AC20C4 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 AC20C4, octal 53020304, decimal 11,280,580.
What flights does AC20C4 operate?
Mode-S AC20C4 has broadcast 20 distinct callsigns, including SWA2004, SWA120, SWA455, SWA3901, SWA3457.