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sensors Mode-S transponder

A18B41

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N199SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A18B41
Octal
50305501
Decimal
10,586,945
Country
US
Tail
N199SY
Type
E75L
Broadcasting now · callsign SKW3250 · 650 ft
Flights observed
630
Distinct callsigns
20
Country
US
Last broadcast
8m ago

Current position

A18B41 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A18B41 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
SKW3066 - 9 2026-07-07
SKW3433 - 7 2026-07-08
SKW3404 SkyWest Airlines 7 2026-06-14
SKW3033 SkyWest Airlines 7 2026-05-28
SKW3374 SkyWest Airlines 6 2026-06-17
SKW3288 - 6 2026-06-28
SKW3118 - 6 2026-07-01
SKW3106 SkyWest Airlines 6 2026-07-09
SKW3079 - 6 2026-07-14
SKW3076 - 6 2026-06-28
SKW3073 SkyWest Airlines 6 2026-06-18
SKW3046 SkyWest Airlines 6 2026-06-07
SKW3009 SkyWest Airlines 6 2026-06-29
SKW3498 - 5 2026-06-22
SKW3445 SkyWest Airlines 5 2026-05-20
SKW3414 SkyWest Airlines 5 2026-05-14
SKW3413 - 5 2026-07-04
SKW3405 SkyWest Airlines 5 2026-05-31
SKW3370 SkyWest Airlines 5 2026-07-10
SKW3322 - 5 2026-06-28

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SKW3250 - Jul 14, 21:45 UTCJul 15, 00:15 UTC2h 29m
2026-07-14 SKW3111 - Jul 14, 19:20 UTCJul 14, 20:35 UTC1h 15m
2026-07-14 SKW3079 - Jul 14, 16:50 UTCJul 14, 18:05 UTC1h 15m
2026-07-14 SKW3385 - Jul 14, 13:25 UTCJul 14, 13:55 UTC30m
2026-07-14 SKW3102 - Jul 14, 04:35 UTCJul 14, 05:00 UTC25m
2026-07-14 SKW3048 EUG → SEA Jul 14, 02:40 UTCJul 14, 03:25 UTC45m
2026-07-13 SKW3107 - Jul 13, 23:50 UTCJul 14, 01:20 UTC1h 30m
2026-07-13 SKW3092 - Jul 13, 21:50 UTCJul 13, 22:55 UTC1h 5m
2026-07-13 SKW3467 - Jul 13, 19:35 UTCJul 13, 20:50 UTC1h 15m
2026-07-13 SKW3450 - Jul 13, 17:05 UTCJul 13, 18:15 UTC1h 10m
2026-07-13 SKW3450 SFO → SNA Jul 13, 17:20 UTCJul 13, 18:05 UTC45m
2026-07-13 SKW3497 - Jul 13, 15:15 UTCJul 13, 16:15 UTC1h 0m
2026-07-12 SKW3081 - Jul 12, 22:50 UTCJul 12, 23:55 UTC1h 5m
2026-07-12 SKW3347 - Jul 12, 20:45 UTCJul 12, 21:55 UTC1h 10m
2026-07-12 SKW3217 EUG → SAN Jul 12, 17:35 UTCJul 12, 19:45 UTC2h 10m
2026-07-12 SKW3319 - Jul 12, 02:35 UTCJul 12, 04:20 UTC1h 45m
2026-07-12 SKW3211 SJC → SAN Jul 12, 00:15 UTCJul 12, 01:30 UTC1h 15m
2026-07-11 SKW3210 PDX → SJC Jul 11, 21:35 UTCJul 11, 23:15 UTC1h 40m
2026-07-11 SKW3045 OAK → PDX Jul 11, 19:10 UTCJul 11, 20:25 UTC1h 15m
2026-07-11 SKW3055 - Jul 11, 16:40 UTCJul 11, 18:20 UTC1h 40m
2026-07-11 SKW3417 - Jul 11, 14:15 UTCJul 11, 15:25 UTC1h 10m
2026-07-11 SKW3115 - Jul 11, 05:01 UTCJul 11, 06:20 UTC1h 20m
2026-07-11 SKW3030 - Jul 11, 01:45 UTCJul 11, 03:05 UTC1h 20m
2026-07-10 SKW3029 - Jul 10, 23:50 UTCJul 11, 00:55 UTC1h 5m
2026-07-10 SKW3123 SLC → SAN Jul 10, 21:00 UTCJul 10, 22:45 UTC1h 45m
2026-07-10 SKW3112 PDX → SLC Jul 10, 18:25 UTCJul 10, 19:55 UTC1h 30m
2026-07-10 SKW3370 PDX → SEA Jul 10, 14:30 UTCJul 10, 16:45 UTC2h 15m
2026-07-10 SKW3022 - Jul 10, 00:55 UTCJul 10, 02:50 UTC1h 55m
2026-07-09 SKW3421 SFO → LAX Jul 9, 22:40 UTCJul 9, 23:45 UTC1h 5m
2026-07-09 SKW3490 STS → SNA Jul 9, 20:06 UTCJul 9, 21:12 UTC1h 6m
2026-07-09 SKW3490 STS → SNA Jul 9, 19:55 UTCJul 9, 20:55 UTC1h 0m
2026-07-09 SKW3100 - Jul 9, 17:45 UTCJul 9, 18:45 UTC1h 0m
2026-07-09 SKW3101 FWA → DFW Jul 9, 15:35 UTCJul 9, 16:20 UTC45m
2026-07-09 SKW3448 - Jul 9, 13:15 UTCJul 9, 13:35 UTC20m
2026-07-09 SKW3106 SAN → SJC Jul 9, 04:45 UTCJul 9, 05:25 UTC40m
2026-07-09 SKW3285 LAX → SEA Jul 9, 01:10 UTCJul 9, 02:35 UTC1h 25m
2026-07-08 SKW3285 LAX → SEA Jul 8, 22:15 UTCJul 8, 23:40 UTC1h 25m
2026-07-08 SKW3121 - Jul 8, 19:10 UTCJul 8, 20:25 UTC1h 15m
2026-07-08 SKW3110 - Jul 8, 16:55 UTCJul 8, 18:00 UTC1h 5m
2026-07-08 SKW3018 SLC → SAN Jul 8, 14:00 UTCJul 8, 15:35 UTC1h 35m
2026-07-08 SKW3298 - Jul 8, 02:10 UTCJul 8, 03:50 UTC1h 40m
2026-07-08 SKW3433 - Jul 8, 00:45 UTCJul 8, 01:10 UTC25m
2026-07-08 SKW3433 BLI → SEA Jul 8, 00:51 UTCJul 8, 01:09 UTC18m
2026-07-07 SKW3433 SEA → BLI Jul 7, 23:25 UTCJul 7, 23:50 UTC25m
2026-07-07 SKW3294 GEG → SEA Jul 7, 21:30 UTCJul 7, 21:55 UTC25m
2026-07-07 SKW3294 GEG → SEA Jul 7, 19:45 UTCJul 7, 20:10 UTC25m
2026-07-07 SKW3089 RNO → SEA Jul 7, 16:40 UTCJul 7, 18:10 UTC1h 30m
2026-07-07 SKW3353 RDM → SFO Jul 7, 14:25 UTCJul 7, 15:25 UTC1h 0m
2026-07-07 SKW3353 RDM → SFO Jul 7, 14:16 UTCJul 7, 15:35 UTC1h 19m
2026-07-07 SKW3109 - Jul 7, 12:35 UTCJul 7, 13:10 UTC35m

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 N199SY page for operator, model, and routing details .

Mode-S A18B41 frequently asked

What is Mode-S code A18B41?
A18B41 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N199SY.
Where is Mode-S A18B41 registered?
Mode-S code A18B41 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 A18B41 broadcasting right now?
Yes. Mode-S A18B41 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A18B41, octal 50305501, decimal 10,586,945.
What flights does A18B41 operate?
Mode-S A18B41 has broadcast 20 distinct callsigns, including SKW3066, SKW3433, SKW3404, SKW3033, SKW3374.