sensors Mode-S transponder

AC33E2

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N8858K · BOEING 737 MAX 8 · operated by SOUTHWEST AIRLINES CO

Hex
AC33E2
Octal
53031742
Decimal
11,285,474
Country
US
Tail
N8858K
Type
B38M
No current signal · last broadcast 16h ago
Flights observed
15
Distinct callsigns
7
Country
US
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S AC33E2.

Country allocation

The ICAO 24-bit address AC33E2 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
SWA2744 - 4 2026-04-13
SWA4209 - 3 2026-04-13
SWA960 - 2 2026-04-13
SWA4529 - 2 2026-04-13
SWA2105 - 2 2026-04-13
SWA660 Southwest Airlines 1 2026-04-14
SWA3555 - 1 2026-04-12

Recent flights last 15

DateFlightRouteTakeoffLandingDuration
2026-04-14 SWA660 SAN → OAK Apr 14, 05:17 UTCApr 14, 06:22 UTC1h 5m
2026-04-13 SWA4529 - Apr 13, 22:30 UTCApr 13, 22:40 UTC10m
2026-04-13 SWA4529 - Apr 13, 20:58 UTCApr 13, 22:12 UTC1h 14m
2026-04-13 SWA2105 - Apr 13, 19:50 UTCApr 13, 20:15 UTC25m
2026-04-13 SWA2105 - Apr 13, 17:15 UTCApr 13, 20:10 UTC2h 55m
2026-04-13 SWA960 - Apr 13, 12:20 UTCApr 13, 15:45 UTC3h 25m
2026-04-13 SWA960 - Apr 13, 11:55 UTCApr 13, 15:32 UTC3h 37m
2026-04-13 SWA4209 - Apr 13, 08:20 UTCApr 13, 09:05 UTC45m
2026-04-13 SWA4209 - Apr 13, 07:55 UTCApr 13, 09:05 UTC1h 10m
2026-04-13 SWA4209 - Apr 13, 04:30 UTCApr 13, 09:24 UTC4h 54m
2026-04-13 SWA2744 - Apr 13, 03:10 UTCApr 13, 03:15 UTC5m
2026-04-13 SWA2744 - Apr 13, 01:36 UTCApr 13, 02:54 UTC1h 18m
2026-04-13 SWA2744 - Apr 13, 00:20 UTCApr 13, 00:50 UTC30m
2026-04-13 SWA2744 LAS → SAN Apr 13, 00:00 UTCApr 13, 00:50 UTC50m
2026-04-12 SWA3555 - Apr 12, 18:18 UTCApr 12, 20:22 UTC2h 4m

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 N8858K page for operator, model, and routing details .

Mode-S AC33E2 frequently asked

What is Mode-S code AC33E2?
AC33E2 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N8858K.
Where is Mode-S AC33E2 registered?
Mode-S code AC33E2 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 AC33E2 broadcasting right now?
No active broadcast right now. Last signal was 16h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AC33E2, octal 53031742, decimal 11,285,474.
What flights does AC33E2 operate?
Mode-S AC33E2 has broadcast 7 distinct callsigns, including SWA2744, SWA4209, SWA960, SWA4529, SWA2105.