sensors Mode-S transponder

AC4843

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N8904L · operated by SOUTHWEST AIRLINES CO

Hex
AC4843
Octal
53044103
Decimal
11,290,691
Country
US
Tail
N8904L
Type
B38M
Transponder active on ground
Flights observed
13
Distinct callsigns
7
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AC4843.

Country allocation

The ICAO 24-bit address AC4843 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 7 distinct

Callsign Airline Flights Last seen
SWA4145 - 3 2026-04-13
SWA4062 - 2 2026-04-12
SWA2220 Southwest Airlines 2 2026-04-13
SWA1527 - 2 2026-04-13
SWA1251 Southwest Airlines 2 2026-04-13
SWA3137 Southwest Airlines 1 2026-04-13
SWA2159 Southwest Airlines 1 2026-04-12

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-13 SWA3137 MDW → OMA Apr 13, 20:41 UTCApr 14, 00:34 UTC3h 53m
2026-04-13 SWA2220 BWI → ALB Apr 13, 19:25 UTCApr 13, 19:40 UTC15m
2026-04-13 SWA2220 BWI → ALB Apr 13, 17:25 UTCApr 13, 18:50 UTC1h 25m
2026-04-13 SWA1527 - Apr 13, 15:50 UTCApr 13, 16:10 UTC20m
2026-04-13 SWA1527 - Apr 13, 14:05 UTCApr 13, 16:10 UTC2h 5m
2026-04-13 SWA4145 - Apr 13, 12:20 UTCApr 13, 12:55 UTC35m
2026-04-13 SWA4145 - Apr 13, 11:55 UTCApr 13, 12:55 UTC1h 0m
2026-04-13 SWA4145 - Apr 13, 10:57 UTCApr 13, 13:04 UTC2h 7m
2026-04-13 SWA1251 OAK → BUR Apr 13, 00:25 UTCApr 13, 02:39 UTC2h 14m
2026-04-13 SWA1251 OAK → BUR Apr 13, 01:00 UTCApr 13, 03:40 UTC2h 40m
2026-04-12 SWA2159 BWI → DAL Apr 12, 18:35 UTCApr 12, 20:15 UTC1h 40m
2026-04-12 SWA4062 - Apr 12, 16:19 UTCApr 12, 17:28 UTC1h 9m
2026-04-12 SWA4062 - Apr 12, 17:15 UTCApr 12, 17:25 UTC10m

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 N8904L page for operator, model, and routing details .

Mode-S AC4843 frequently asked

What is Mode-S code AC4843?
AC4843 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N8904L.
Where is Mode-S AC4843 registered?
Mode-S code AC4843 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 AC4843 broadcasting right now?
Mode-S AC4843 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC4843, octal 53044103, decimal 11,290,691.
What flights does AC4843 operate?
Mode-S AC4843 has broadcast 7 distinct callsigns, including SWA4145, SWA4062, SWA2220, SWA1527, SWA1251.