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sensors Mode-S transponder

A2355D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N241SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A2355D
Octal
50432535
Decimal
10,630,493
Country
US
Tail
N241SY
Type
E75L
No current signal · last broadcast Jul 22, 16:55 UTC
Flights observed
628
Distinct callsigns
20
Country
US
Last broadcast
Jul 22, 16:55 UTC

Last known position

Most recent position reported by Mode-S A2355D.

Country allocation

The ICAO 24-bit address A2355D 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
SKW3923 SkyWest Airlines 13 2026-07-20
SKW3755 - 11 2026-07-11
SKW3999 - 10 2026-07-07
SKW3894 - 9 2026-07-05
SKW4155 SkyWest Airlines 8 2026-04-29
SKW3902 - 8 2026-06-26
SKW3883 - 8 2026-06-28
SKW3913 - 7 2026-07-09
SKW3818 SkyWest Airlines 7 2026-07-02
SKW3754 - 7 2026-07-01
SKW4471 - 6 2026-07-12
SKW4165 SkyWest Airlines 6 2026-07-20
SKW4144 SkyWest Airlines 6 2026-04-29
SKW4119 - 6 2026-06-26
SKW4077 - 6 2026-06-27
SKW4057 - 6 2026-06-27
SKW3989 SkyWest Airlines 6 2026-06-03
SKW3842 - 6 2026-06-28
SKW3824 - 6 2026-06-20
SKW3707 - 6 2026-07-02

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-22 SKW102P SGU → SLC Jul 22, 16:00 UTCJul 22, 16:55 UTC55m
2026-07-21 SKW160Y - Jul 21, 01:15 UTCJul 21, 02:00 UTC45m
2026-07-20 SKW3895 DTW → ALB Jul 20, 23:20 UTCJul 20, 23:45 UTC25m
2026-07-20 SKW3895 DTW → ALB Jul 20, 23:22 UTCJul 20, 23:52 UTC30m
2026-07-20 SKW4104 ORD → JFK Jul 20, 19:05 UTCJul 20, 22:25 UTC3h 20m
2026-07-20 SKW3953 JFK → ORD Jul 20, 16:45 UTCJul 20, 17:15 UTC30m
2026-07-20 SKW3953 JFK → ORD Jul 20, 14:50 UTCJul 20, 15:20 UTC30m
2026-07-20 SKW4008 PDX → SEA Jul 20, 12:50 UTCJul 20, 13:20 UTC30m
2026-07-20 SKW4472 SEA → PDX Jul 20, 06:20 UTCJul 20, 06:50 UTC30m
2026-07-20 SKW3923 OAK → LAX Jul 20, 04:45 UTCJul 20, 05:10 UTC25m
2026-07-20 SKW3923 OAK → LAX Jul 20, 02:15 UTCJul 20, 02:50 UTC35m
2026-07-20 SKW4165 MSN → MSP Jul 20, 00:00 UTCJul 20, 00:50 UTC50m
2026-07-19 SKW4145 SEA → GEG Jul 19, 22:15 UTCJul 19, 22:55 UTC40m
2026-07-19 SKW3878 CLE → LGA Jul 19, 19:30 UTCJul 19, 20:20 UTC50m
2026-07-19 SKW3806 LAX → OAK Jul 19, 18:10 UTCJul 19, 18:30 UTC20m
2026-07-19 SKW3806 LAX → OAK Jul 19, 17:05 UTCJul 19, 17:40 UTC35m
2026-07-19 SKW3806 LAX → OAK Jul 19, 17:09 UTCJul 19, 18:27 UTC1h 18m
2026-07-19 SKW4006 - Jul 19, 13:15 UTCJul 19, 15:30 UTC2h 15m
2026-07-18 SKW3825 MSP → MOT Jul 18, 23:25 UTCJul 19, 01:35 UTC2h 10m
2026-07-18 SKW3833 - Jul 18, 19:25 UTCJul 18, 20:40 UTC1h 15m
2026-07-18 SKW3833 - Jul 18, 17:00 UTCJul 18, 17:55 UTC55m
2026-07-18 SKW4029 SJC → SLC Jul 18, 13:40 UTCJul 18, 15:40 UTC2h 0m
2026-07-18 SKW3703 SLC → OKC Jul 18, 02:50 UTCJul 18, 04:45 UTC1h 55m
2026-07-18 SKW144J LGB → SLC Jul 18, 00:15 UTCJul 18, 01:45 UTC1h 30m
2026-07-17 SKW108R SLC → LGB Jul 17, 21:15 UTCJul 17, 23:05 UTC1h 50m
2026-07-17 SKW3815 DLH → MSP Jul 17, 17:50 UTCJul 17, 20:00 UTC2h 10m
2026-07-17 SKW3815 DLH → MSP Jul 17, 17:55 UTCJul 17, 19:53 UTC1h 58m
2026-07-17 SKW3838 MSP → OMA Jul 17, 16:05 UTCJul 17, 16:39 UTC34m
2026-07-17 SKW3838 - Jul 17, 15:55 UTCJul 17, 16:40 UTC45m
2026-07-17 SKW4458 - Jul 17, 13:05 UTCJul 17, 14:00 UTC55m
2026-07-17 SKW4458 MKE → MSP Jul 17, 13:10 UTCJul 17, 13:56 UTC46m
2026-07-17 SKW4468 MSP → MKE Jul 17, 01:35 UTCJul 17, 02:25 UTC50m
2026-07-16 SKW3526 YWG → MSP Jul 16, 21:15 UTCJul 16, 22:15 UTC1h 0m
2026-07-16 SKW3526 YWG → MSP Jul 16, 21:16 UTCJul 16, 22:10 UTC54m
2026-07-16 SKW192E MSP → YWG Jul 16, 18:59 UTCJul 16, 20:05 UTC1h 5m
2026-07-16 SKW3813 AUS → MSP Jul 16, 15:05 UTCJul 16, 17:40 UTC2h 35m
2026-07-16 SKW4015 - Jul 16, 11:50 UTCJul 16, 13:49 UTC2h 0m
2026-07-16 SKW3731 AUS → IND Jul 16, 00:25 UTCJul 16, 02:35 UTC2h 10m
2026-07-15 SKW4053 - Jul 15, 22:15 UTCJul 15, 23:05 UTC50m
2026-07-15 SKW4053 - Jul 15, 20:10 UTCJul 15, 20:55 UTC45m
2026-07-15 SKW3747 - Jul 15, 16:50 UTCJul 15, 18:50 UTC2h 0m
2026-07-15 SKW3747 AUS → PHX Jul 15, 13:50 UTCJul 15, 15:55 UTC2h 5m
2026-07-15 SKW3945 - Jul 15, 00:20 UTCJul 15, 02:15 UTC1h 55m
2026-07-14 SKW3945 AUS → BNA Jul 14, 21:25 UTCJul 14, 23:20 UTC1h 54m
2026-07-14 SKW3955 SLC → AUS Jul 14, 17:41 UTCJul 14, 19:57 UTC2h 16m
2026-07-14 SKW3955 SLC → AUS Jul 14, 17:35 UTCJul 14, 20:00 UTC2h 25m
2026-07-14 SKW3937 SJC → SLC Jul 14, 02:15 UTCJul 14, 03:40 UTC1h 25m
2026-07-13 SKW3937 SLC → SJC Jul 13, 23:40 UTCJul 14, 01:15 UTC1h 35m
2026-07-13 SKW3801 MFR → SLC Jul 13, 20:50 UTCJul 13, 22:15 UTC1h 25m
2026-07-13 SKW3779 - Jul 13, 18:30 UTCJul 13, 19:40 UTC1h 10m

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 N241SY page for operator, model, and routing details .

Mode-S A2355D frequently asked

What is Mode-S code A2355D?
A2355D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N241SY.
Where is Mode-S A2355D registered?
Mode-S code A2355D 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 A2355D broadcasting right now?
No active broadcast right now. Last signal was Jul 22, 16:55 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A2355D, octal 50432535, decimal 10,630,493.
What flights does A2355D operate?
Mode-S A2355D has broadcast 20 distinct callsigns, including SKW3923, SKW3755, SKW3999, SKW3894, SKW4155.