Apparatus

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sensors Mode-S transponder

A66E3B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N513SY · EMBRAER ERJ-170-200 (long wing) · operated by SKYWEST AIRLINES INC

Hex
A66E3B
Octal
51467073
Decimal
10,907,195
Country
US
Tail
N513SY
Type
E75L
Broadcasting now · callsign SKW4971 · 36,000 ft
Flights observed
661
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 22:30 UTC

Current position

A66E3B is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A66E3B 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
SKW4958 SkyWest Airlines 23 2026-07-20
SKW6315 SkyWest Airlines 20 2026-07-24
SKW4977 SkyWest Airlines 20 2026-07-26
SKW4925 - 18 2026-07-18
SKW6425 SkyWest Airlines 17 2026-07-23
SKW4957 - 17 2026-06-28
SKW6190 - 14 2026-06-28
SKW4995 SkyWest Airlines 14 2026-07-17
SKW6227 SkyWest Airlines 13 2026-07-19
SKW6213 SkyWest Airlines 12 2026-04-15
SKW4968 SkyWest Airlines 12 2026-07-19
SKW6212 SkyWest Airlines 11 2026-04-17
SKW6185 SkyWest Airlines 11 2026-07-22
SKW6393 SkyWest Airlines 10 2026-07-24
SKW6353 SkyWest Airlines 10 2026-05-13
SKW6224 - 10 2026-07-10
SKW4906 - 10 2026-07-07
SKW6278 - 9 2026-06-21
SKW6272 SkyWest Airlines 9 2026-07-21
SKW6270 SkyWest Airlines 9 2026-07-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 SKW6221 FAT → PHX Jul 26, 21:30 UTCJul 26, 22:30 UTC1h 0m
2026-07-26 SKW4977 HRL → ORD Jul 26, 15:35 UTCJul 26, 20:10 UTC4h 35m
2026-07-26 SKW6294 SFO → LAX Jul 26, 13:15 UTCJul 26, 14:20 UTC1h 5m
2026-07-26 SKW6294 SFO → LAX Jul 26, 13:15 UTCJul 26, 14:19 UTC1h 4m
2026-07-26 SKW6510 LAX → SFO Jul 26, 05:40 UTCJul 26, 06:35 UTC56m
2026-07-26 SKW6510 LAX → SFO Jul 26, 05:50 UTCJul 26, 06:38 UTC48m
2026-07-26 SKW5005 PHX → STS Jul 26, 01:35 UTCJul 26, 04:35 UTC3h 0m
2026-07-25 SKW5005 PHX → STS Jul 25, 21:25 UTCJul 26, 00:35 UTC3h 10m
2026-07-25 SKW6482 ASE → AUS Jul 25, 12:20 UTCJul 25, 15:25 UTC3h 5m
2026-07-25 SKW6187 DFW → PVU Jul 25, 01:00 UTCJul 25, 03:55 UTC2h 55m
2026-07-24 SKW6366 AUS → DFW Jul 24, 20:55 UTCJul 24, 23:55 UTC3h 0m
2026-07-24 SKW6366 AUS → DFW Jul 24, 20:44 UTCJul 24, 23:41 UTC2h 57m
2026-07-24 SKW6366 AUS → DFW Jul 24, 17:05 UTCJul 24, 20:00 UTC2h 55m
2026-07-24 SKW6393 TUS → LAX Jul 24, 13:15 UTCJul 24, 14:30 UTC1h 15m
2026-07-24 SKW6393 TUS → LAX Jul 24, 13:12 UTCJul 24, 14:19 UTC1h 7m
2026-07-24 SKW6315 LAX → ABQ Jul 24, 03:00 UTCJul 24, 04:15 UTC1h 15m
2026-07-23 SKW6270 LAX → SFO Jul 23, 23:35 UTCJul 24, 01:55 UTC2h 20m
2026-07-23 SKW6270 LAX → SFO Jul 23, 20:25 UTCJul 23, 22:15 UTC1h 50m
2026-07-23 SKW6425 MAF → DFW Jul 23, 17:20 UTCJul 23, 18:05 UTC45m
2026-07-23 SKW6425 MAF → DFW Jul 23, 15:35 UTCJul 23, 16:20 UTC45m
2026-07-23 SKW6346 ORD → BNA Jul 23, 02:25 UTCJul 23, 03:30 UTC1h 5m
2026-07-23 SKW6346 ORD → BNA Jul 23, 02:24 UTCJul 23, 03:28 UTC1h 4m
2026-07-23 SKW6346 ORD → BNA Jul 23, 00:25 UTCJul 23, 01:30 UTC1h 5m
2026-07-22 SKW6307 DFW → SHV Jul 22, 20:20 UTCJul 22, 22:55 UTC2h 35m
2026-07-22 SKW6307 DFW → SHV Jul 22, 16:45 UTCJul 22, 19:20 UTC2h 35m
2026-07-22 SKW6185 SFO → LAX Jul 22, 12:20 UTCJul 22, 14:55 UTC2h 35m
2026-07-21 SKW4979 DFW → MLU Jul 21, 23:45 UTCJul 22, 02:35 UTC2h 50m
2026-07-21 SKW4979 DFW → MLU Jul 21, 23:40 UTCJul 22, 02:34 UTC2h 54m
2026-07-21 SKW6272 MRY → PHX Jul 21, 19:30 UTCJul 21, 22:10 UTC2h 40m
2026-07-21 SKW6272 MRY → PHX Jul 21, 19:36 UTCJul 21, 22:02 UTC2h 26m
2026-07-21 SKW6272 MRY → PHX Jul 21, 15:55 UTCJul 21, 18:30 UTC2h 35m
2026-07-21 SKW6294 SFO → LAX Jul 21, 13:15 UTCJul 21, 14:15 UTC1h 0m
2026-07-21 SKW6510 LAX → SFO Jul 21, 06:05 UTCJul 21, 06:55 UTC50m
2026-07-21 SKW4971 DFW → LRD Jul 21, 00:00 UTCJul 21, 03:05 UTC3h 5m
2026-07-20 SKW4971 DFW → LRD Jul 20, 19:45 UTCJul 20, 22:50 UTC3h 5m
2026-07-20 SKW6425 MAF → DFW Jul 20, 17:30 UTCJul 20, 18:10 UTC40m
2026-07-20 SKW6425 MAF → DFW Jul 20, 17:28 UTCJul 20, 18:10 UTC42m
2026-07-20 SKW6425 MAF → DFW Jul 20, 15:25 UTCJul 20, 16:15 UTC50m
2026-07-20 SKW4958 ORD → MKE Jul 20, 03:10 UTCJul 20, 05:00 UTC1h 50m
2026-07-20 SKW4958 ORD → MKE Jul 20, 03:08 UTCJul 20, 04:58 UTC1h 50m
2026-07-20 SKW4958 ORD → MKE Jul 20, 00:10 UTCJul 20, 02:15 UTC2h 5m
2026-07-19 SKW4977 - Jul 19, 18:45 UTCJul 19, 23:10 UTC4h 25m
2026-07-19 SKW6227 MCI → ORD Jul 19, 14:55 UTCJul 19, 17:35 UTC2h 40m
2026-07-19 SKW6420 SEA → LAX Jul 19, 05:15 UTCJul 19, 07:42 UTC2h 27m
2026-07-19 SKW6420 SEA → LAX Jul 19, 05:10 UTCJul 19, 07:40 UTC2h 30m
2026-07-19 SKW6368 - Jul 19, 03:40 UTCJul 19, 04:10 UTC30m
2026-07-19 SKW6370 - Jul 19, 02:25 UTCJul 19, 02:50 UTC25m
2026-07-19 SKW4968 LEX → ORD Jul 19, 00:05 UTCJul 19, 00:45 UTC40m
2026-07-19 SKW4968 LEX → ORD Jul 19, 00:00 UTCJul 19, 01:17 UTC1h 17m
2026-07-18 SKW4968 LEX → ORD Jul 18, 21:35 UTCJul 18, 22:45 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 N513SY page for operator, model, and routing details .

Mode-S A66E3B frequently asked

What is Mode-S code A66E3B?
A66E3B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N513SY.
Where is Mode-S A66E3B registered?
Mode-S code A66E3B 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 A66E3B broadcasting right now?
Yes. Mode-S A66E3B is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A66E3B, octal 51467073, decimal 10,907,195.
What flights does A66E3B operate?
Mode-S A66E3B has broadcast 20 distinct callsigns, including SKW4958, SKW6315, SKW4977, SKW4925, SKW6425.