sensors Mode-S transponder

A309B4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N295SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A309B4
Octal
50604664
Decimal
10,684,852
Country
US
Tail
N295SY
Type
E75L
No current signal · last broadcast 4h ago
Flights observed
616
Distinct callsigns
20
Country
US
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S A309B4.

Country allocation

The ICAO 24-bit address A309B4 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
SKW4032 - 11 2026-06-19
SKW3989 - 10 2026-07-10
SKW3899 - 9 2026-07-12
SKW4177 - 8 2026-06-15
SKW4462 SkyWest Airlines 7 2026-06-21
SKW4063 SkyWest Airlines 7 2026-05-08
SKW3526 - 7 2026-07-12
SKW4153 SkyWest Airlines 6 2026-06-03
SKW4099 - 6 2026-07-03
SKW4068 SkyWest Airlines 6 2026-06-03
SKW4035 - 6 2026-07-12
SKW3945 SkyWest Airlines 6 2026-07-05
SKW3935 - 6 2026-07-10
SKW3902 - 6 2026-07-03
SKW3666 SkyWest Airlines 6 2026-06-13
SKW4119 SkyWest Airlines 5 2026-05-27
SKW4077 SkyWest Airlines 5 2026-05-27
SKW4076 SkyWest Airlines 5 2026-05-23
SKW4041 SkyWest Airlines 5 2026-06-03
SKW4015 - 5 2026-07-09

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SKW144J LGB → SLC Jul 14, 00:05 UTCJul 14, 01:25 UTC1h 20m
2026-07-13 SKW108R SLC → LGB Jul 13, 21:25 UTCJul 13, 23:00 UTC1h 35m
2026-07-13 SKW108R SLC → LGB Jul 13, 21:15 UTCJul 13, 22:49 UTC1h 34m
2026-07-13 SKW3815 - Jul 13, 17:50 UTCJul 13, 19:55 UTC2h 5m
2026-07-13 SKW3815 OMA → SLC Jul 13, 17:55 UTCJul 13, 19:52 UTC1h 57m
2026-07-13 SKW3838 - Jul 13, 15:55 UTCJul 13, 16:45 UTC50m
2026-07-13 SKW3844 OKC → MSP Jul 13, 12:55 UTCJul 13, 14:35 UTC1h 40m
2026-07-13 SKW3791 MSP → OKC Jul 13, 01:10 UTCJul 13, 02:45 UTC1h 35m
2026-07-12 SKW3526 YWG → MSP Jul 12, 21:00 UTCJul 12, 22:25 UTC1h 25m
2026-07-12 SKW192E MSP → YWG Jul 12, 19:01 UTCJul 12, 20:05 UTC1h 5m
2026-07-12 SKW3561 BOI → SEA Jul 12, 16:05 UTCJul 12, 16:45 UTC40m
2026-07-12 SKW3561 BOI → SEA Jul 12, 16:15 UTCJul 12, 16:40 UTC25m
2026-07-12 SKW3561 BOI → SEA Jul 12, 14:40 UTCJul 12, 15:10 UTC30m
2026-07-12 SKW3899 - Jul 12, 11:10 UTCJul 12, 12:50 UTC1h 40m
2026-07-12 SKW4035 MSP → MEM Jul 12, 01:35 UTCJul 12, 02:52 UTC1h 17m
2026-07-12 SKW4035 - Jul 12, 01:20 UTCJul 12, 02:50 UTC1h 30m
2026-07-11 SKW4116 - Jul 11, 23:30 UTCJul 12, 00:15 UTC45m
2026-07-11 SKW4116 MSN → MSP Jul 11, 23:36 UTCJul 12, 00:07 UTC31m
2026-07-11 SKW3854 MSP → MSN Jul 11, 21:29 UTCJul 11, 21:54 UTC25m
2026-07-11 SKW3854 - Jul 11, 21:20 UTCJul 11, 22:01 UTC40m
2026-07-11 SKW3536 XNA → MSP Jul 11, 16:55 UTCJul 11, 18:30 UTC1h 35m
2026-07-11 SKW3536 MSP → XNA Jul 11, 14:30 UTCJul 11, 15:50 UTC1h 20m
2026-07-11 SKW3899 - Jul 11, 11:20 UTCJul 11, 13:05 UTC1h 45m
2026-07-11 SKW3899 MEM → MSP Jul 11, 11:23 UTCJul 11, 13:02 UTC1h 39m
2026-07-11 SKW4035 - Jul 11, 01:15 UTCJul 11, 02:50 UTC1h 35m
2026-07-10 SKW3935 - Jul 10, 23:25 UTCJul 11, 00:10 UTC45m
2026-07-10 SKW3935 - Jul 10, 20:35 UTCJul 10, 21:25 UTC50m
2026-07-10 SKW3989 - Jul 10, 17:20 UTCJul 10, 18:55 UTC1h 35m
2026-07-10 SKW3989 MEM → MSP Jul 10, 17:24 UTCJul 10, 18:50 UTC1h 26m
2026-07-10 SKW3989 - Jul 10, 14:25 UTCJul 10, 16:00 UTC1h 35m
2026-07-10 SKW3899 - Jul 10, 11:05 UTCJul 10, 12:50 UTC1h 45m
2026-07-10 SKW4035 - Jul 10, 01:20 UTCJul 10, 02:55 UTC1h 35m
2026-07-09 SKW3526 YWG → MSP Jul 9, 21:45 UTCJul 9, 22:45 UTC1h 0m
2026-07-09 SKW3526 YWG → MSP Jul 9, 21:46 UTCJul 9, 22:39 UTC53m
2026-07-09 SKW192E MSP → YWG Jul 9, 18:50 UTCJul 9, 20:00 UTC1h 10m
2026-07-09 SKW3813 AUS → MSP Jul 9, 15:05 UTCJul 9, 17:30 UTC2h 25m
2026-07-09 SKW4015 - Jul 9, 11:55 UTCJul 9, 14:00 UTC2h 5m
2026-07-09 SKW3731 AUS → IND Jul 9, 00:35 UTCJul 9, 02:40 UTC2h 5m
2026-07-08 SKW4016 MSY → AUS Jul 8, 21:15 UTCJul 8, 22:25 UTC1h 10m
2026-07-08 SKW141E AUS → MSY Jul 8, 18:30 UTCJul 8, 19:50 UTC1h 20m
2026-07-08 SKW141E AUS → MSY Jul 8, 18:32 UTCJul 8, 19:45 UTC1h 13m
2026-07-08 SKW3876 DEN → AUS Jul 8, 15:45 UTCJul 8, 17:30 UTC1h 45m
2026-07-08 SKW3876 AUS → DEN Jul 8, 12:55 UTCJul 8, 14:45 UTC1h 50m
2026-07-08 SKW3577 - Jul 8, 01:00 UTCJul 8, 02:25 UTC1h 25m
2026-07-07 SKW3577 - Jul 7, 22:20 UTCJul 8, 00:00 UTC1h 40m
2026-07-07 SKW3772 - Jul 7, 18:40 UTCJul 7, 21:00 UTC2h 20m
2026-07-07 SKW107K - Jul 7, 15:30 UTCJul 7, 17:40 UTC2h 10m
2026-07-07 SKW4146 BNA → AUS Jul 7, 12:30 UTCJul 7, 14:20 UTC1h 50m
2026-07-07 SKW4163 AUS → BNA Jul 7, 00:30 UTCJul 7, 02:20 UTC1h 50m
2026-07-06 SKW3767 - Jul 6, 21:00 UTCJul 6, 22:50 UTC1h 50m

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 N295SY page for operator, model, and routing details .

Mode-S A309B4 frequently asked

What is Mode-S code A309B4?
A309B4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N295SY.
Where is Mode-S A309B4 registered?
Mode-S code A309B4 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 A309B4 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 A309B4, octal 50604664, decimal 10,684,852.
What flights does A309B4 operate?
Mode-S A309B4 has broadcast 20 distinct callsigns, including SKW4032, SKW3989, SKW3899, SKW4177, SKW4462.