sensors Mode-S transponder

A23CCB

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N243SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A23CCB
Octal
50436313
Decimal
10,632,395
Country
US
Tail
N243SY
Type
E75L
No current signal · last broadcast 20h ago
Flights observed
10
Distinct callsigns
7
Country
US
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S A23CCB.

Country allocation

The ICAO 24-bit address A23CCB 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
SKW3937 - 2 2026-04-13
SKW3819 SkyWest Airlines 2 2026-04-13
SKW3685 - 2 2026-04-13
SKW4169 - 1 2026-04-13
SKW3976 - 1 2026-04-12
SKW3920 - 1 2026-04-12
SKW3914 - 1 2026-04-14

Recent flights last 10

DateFlightRouteTakeoffLandingDuration
2026-04-14 SKW3914 - Apr 14, 10:25 UTCApr 14, 11:05 UTC40m
2026-04-13 SKW4169 MSP → MDW Apr 13, 22:15 UTCApr 13, 23:40 UTC1h 25m
2026-04-13 SKW3819 SJC → LAX Apr 13, 19:45 UTCApr 13, 20:10 UTC25m
2026-04-13 SKW3819 SJC → LAX Apr 13, 17:20 UTCApr 13, 18:45 UTC1h 25m
2026-04-13 SKW3685 - Apr 13, 15:50 UTCApr 13, 16:20 UTC30m
2026-04-13 SKW3685 - Apr 13, 13:30 UTCApr 13, 16:15 UTC2h 45m
2026-04-13 SKW3937 - Apr 13, 00:20 UTCApr 13, 02:45 UTC2h 25m
2026-04-12 SKW3937 - Apr 12, 23:55 UTCApr 13, 02:45 UTC2h 50m
2026-04-12 SKW3976 - Apr 12, 19:10 UTCApr 12, 19:55 UTC45m
2026-04-12 SKW3920 - Apr 12, 17:25 UTCApr 12, 18:15 UTC50m

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 N243SY page for operator, model, and routing details .

Mode-S A23CCB frequently asked

What is Mode-S code A23CCB?
A23CCB is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N243SY.
Where is Mode-S A23CCB registered?
Mode-S code A23CCB 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 A23CCB broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A23CCB, octal 50436313, decimal 10,632,395.
What flights does A23CCB operate?
Mode-S A23CCB has broadcast 7 distinct callsigns, including SKW3937, SKW3819, SKW3685, SKW4169, SKW3976.