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sensors Mode-S transponder

A2644A

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N253SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A2644A
Octal
50462112
Decimal
10,642,506
Country
US
Tail
N253SY
Type
E75L
No current signal · last broadcast 2h ago
Flights observed
582
Distinct callsigns
20
Country
US
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S A2644A.

Country allocation

The ICAO 24-bit address A2644A 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
SKW4099 - 9 2026-06-29
SKW3991 - 9 2026-07-12
SKW3833 SkyWest Airlines 9 2026-07-06
SKW3903 - 8 2026-06-25
SKW3681 - 8 2026-06-23
SKW3828 - 7 2026-07-07
SKW3779 - 7 2026-07-03
SKW3755 - 7 2026-07-13
SKW3669 SkyWest Airlines 7 2026-05-30
SKW3620 - 7 2026-07-04
SKW4444 SkyWest Airlines 6 2026-06-25
SKW3902 SkyWest Airlines 6 2026-05-09
SKW3894 - 6 2026-07-13
SKW3777 - 6 2026-06-19
SKW3765 SkyWest Airlines 6 2026-06-23
SKW3725 - 6 2026-07-13
SKW3680 SkyWest Airlines 6 2026-05-07
SKW102P - 6 2026-07-07
SKW4119 SkyWest Airlines 5 2026-05-10
SKW4114 SkyWest Airlines 5 2026-05-04

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SKW4087 - Jul 14, 01:35 UTCJul 14, 02:05 UTC30m
2026-07-13 SKW3894 - Jul 13, 23:15 UTCJul 14, 00:10 UTC55m
2026-07-13 SKW3894 - Jul 13, 21:00 UTCJul 13, 22:10 UTC1h 10m
2026-07-13 SKW3755 SMF → LAX Jul 13, 18:36 UTCJul 13, 19:35 UTC59m
2026-07-13 SKW3755 - Jul 13, 18:25 UTCJul 13, 19:35 UTC1h 10m
2026-07-13 SKW3755 - Jul 13, 16:15 UTCJul 13, 17:20 UTC1h 5m
2026-07-13 SKW3725 - Jul 13, 14:05 UTCJul 13, 15:10 UTC1h 5m
2026-07-13 SKW3725 - Jul 13, 13:15 UTCJul 13, 13:30 UTC15m
2026-07-13 SKW3692 - Jul 13, 03:05 UTCJul 13, 04:10 UTC1h 5m
2026-07-13 SKW127T MFR → SEA Jul 13, 00:45 UTCJul 13, 01:26 UTC41m
2026-07-13 SKW127T MFR → SEA Jul 13, 00:40 UTCJul 13, 01:35 UTC55m
2026-07-12 SKW3770 SEA → MFR Jul 12, 22:20 UTCJul 12, 23:35 UTC1h 15m
2026-07-12 SKW3966 - Jul 12, 19:05 UTCJul 12, 21:10 UTC2h 5m
2026-07-12 SKW3966 SNA → SEA Jul 12, 18:42 UTCJul 12, 21:07 UTC2h 25m
2026-07-12 SKW3966 - Jul 12, 15:01 UTCJul 12, 17:40 UTC2h 40m
2026-07-12 SKW3991 - Jul 12, 04:50 UTCJul 12, 06:20 UTC1h 30m
2026-07-12 SKW3991 SEA → SFO Jul 12, 01:55 UTCJul 12, 03:55 UTC2h 0m
2026-07-11 SKW142Y YVR → SEA Jul 11, 22:50 UTCJul 11, 23:20 UTC30m
2026-07-11 SKW3748 SEA → YVR Jul 11, 20:50 UTCJul 11, 21:20 UTC30m
2026-07-11 SKW156H GEG → SEA Jul 11, 16:40 UTCJul 11, 17:30 UTC50m
2026-07-11 SKW3830 SEA → GEG Jul 11, 14:35 UTCJul 11, 15:15 UTC40m
2026-07-11 SKW3991 - Jul 11, 04:50 UTCJul 11, 06:15 UTC1h 25m
2026-07-11 SKW3991 SFO → SEA Jul 11, 04:44 UTCJul 11, 06:12 UTC1h 28m
2026-07-11 SKW3991 - Jul 11, 01:45 UTCJul 11, 03:45 UTC2h 0m
2026-07-10 SKW3789 - Jul 10, 23:50 UTCJul 10, 23:55 UTC5m
2026-07-10 SKW3789 SJC → SEA Jul 10, 22:05 UTCJul 10, 23:55 UTC1h 50m
2026-07-10 SKW3789 SJC → SEA Jul 10, 22:07 UTCJul 10, 23:32 UTC1h 25m
2026-07-10 SKW168F SEA → SJC Jul 10, 19:25 UTCJul 10, 21:15 UTC1h 50m
2026-07-10 SKW168F SEA → SJC Jul 10, 19:06 UTCJul 10, 21:06 UTC2h 0m
2026-07-10 SKW156H GEG → SEA Jul 10, 16:45 UTCJul 10, 17:35 UTC50m
2026-07-10 SKW3830 SEA → GEG Jul 10, 14:40 UTCJul 10, 15:20 UTC40m
2026-07-10 SKW3830 SEA → GEG Jul 10, 14:30 UTCJul 10, 15:20 UTC50m
2026-07-10 SKW3991 - Jul 10, 06:00 UTCJul 10, 07:30 UTC1h 30m
2026-07-10 SKW3991 SEA → SFO Jul 10, 03:15 UTCJul 10, 05:05 UTC1h 50m
2026-07-10 SKW4153 SMF → SEA Jul 10, 00:30 UTCJul 10, 02:00 UTC1h 30m
2026-07-10 SKW4153 SMF → SEA Jul 10, 00:28 UTCJul 10, 01:58 UTC1h 30m
2026-07-09 SKW4153 SEA → SMF Jul 9, 21:55 UTCJul 9, 23:15 UTC1h 20m
2026-07-09 SKW3878 MFR → SEA Jul 9, 19:45 UTCJul 9, 20:45 UTC1h 0m
2026-07-09 SKW3806 SLC → MFR Jul 9, 17:05 UTCJul 9, 18:30 UTC1h 25m
2026-07-09 SKW3874 - Jul 9, 13:30 UTCJul 9, 15:55 UTC2h 25m
2026-07-09 SKW3706 - Jul 9, 02:45 UTCJul 9, 04:50 UTC2h 5m
2026-07-09 SKW144J LGB → SLC Jul 9, 00:05 UTCJul 9, 01:30 UTC1h 25m
2026-07-08 SKW108R SLC → LGB Jul 8, 21:20 UTCJul 8, 22:55 UTC1h 35m
2026-07-08 SKW3880 SLC → SLC Jul 8, 16:55 UTCJul 8, 20:20 UTC3h 25m
2026-07-08 SKW4029 OKC → SLC Jul 8, 13:35 UTCJul 8, 15:40 UTC2h 5m
2026-07-08 SKW3703 SLC → OKC Jul 8, 02:45 UTCJul 8, 04:40 UTC1h 55m
2026-07-07 SKW3820 ABQ → SLC Jul 7, 23:00 UTCJul 8, 00:15 UTC1h 15m
2026-07-07 SKW3820 ABQ → SLC Jul 7, 22:44 UTCJul 8, 00:15 UTC1h 31m
2026-07-07 SKW3820 SLC → ABQ Jul 7, 20:25 UTCJul 7, 21:55 UTC1h 30m
2026-07-07 SKW4038 - Jul 7, 17:55 UTCJul 7, 19:00 UTC1h 5m

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 N253SY page for operator, model, and routing details .

Mode-S A2644A frequently asked

What is Mode-S code A2644A?
A2644A is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N253SY.
Where is Mode-S A2644A registered?
Mode-S code A2644A 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 A2644A broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2644A, octal 50462112, decimal 10,642,506.
What flights does A2644A operate?
Mode-S A2644A has broadcast 20 distinct callsigns, including SKW4099, SKW3991, SKW3833, SKW3903, SKW3681.