sensors Mode-S transponder

A85D1B

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N638SY · operated by SKYWEST AIRLINES INC

Hex
A85D1B
Octal
52056433
Decimal
11,033,883
Country
US
Tail
N638SY
No current signal · last broadcast 1h ago
Flights observed
627
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A85D1B.

Country allocation

The ICAO 24-bit address A85D1B 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
SKW5329 - 13 2026-07-10
SKW5787 - 11 2026-07-10
SKW5779 - 10 2026-06-30
SKW5775 - 10 2026-07-10
SKW5940 - 9 2026-07-10
SKW5771 - 9 2026-07-09
SKW5914 SkyWest Airlines 8 2026-06-07
SKW5776 SkyWest Airlines 8 2026-07-10
SKW5694 - 8 2026-07-06
SKW5444 SkyWest Airlines 8 2026-07-07
SKW4761 - 8 2026-07-04
SKW4669 - 8 2026-07-12
SKW5993 - 7 2026-06-18
SKW5782 SkyWest Airlines 7 2026-06-08
SKW5772 - 7 2026-07-08
SKW5770 SkyWest Airlines 7 2026-07-02
SKW5774 - 6 2026-07-02
SKW5769 - 6 2026-07-02
SKW5766 - 6 2026-06-30
SKW5759 - 6 2026-06-27

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SKW5582 - Jul 14, 00:05 UTCJul 14, 00:45 UTC40m
2026-07-13 SKW4766 ORD → OKC Jul 13, 21:15 UTCJul 13, 22:55 UTC1h 40m
2026-07-13 SKW5447 - Jul 13, 17:40 UTCJul 13, 18:20 UTC40m
2026-07-13 SKW318J - Jul 13, 16:05 UTCJul 13, 16:35 UTC30m
2026-07-13 SKW318J ORD → MSN Jul 13, 16:14 UTCJul 13, 16:28 UTC14m
2026-07-13 SKW5491 YWG → ORD Jul 13, 12:10 UTCJul 13, 14:05 UTC1h 55m
2026-07-13 SKW5645 ORD → YWG Jul 13, 01:38 UTCJul 13, 03:15 UTC1h 37m
2026-07-13 SKW5645 ORD → YWG Jul 13, 01:35 UTCJul 13, 03:15 UTC1h 40m
2026-07-12 SKW5524 GSP → ORD Jul 12, 21:50 UTCJul 12, 23:50 UTC2h 0m
2026-07-12 SKW5403 - Jul 12, 19:25 UTCJul 12, 20:55 UTC1h 30m
2026-07-12 SKW4669 - Jul 12, 17:45 UTCJul 12, 17:55 UTC10m
2026-07-12 SKW4669 - Jul 12, 15:25 UTCJul 12, 17:55 UTC2h 30m
2026-07-12 SKW4669 ASE → ORD Jul 12, 15:25 UTCJul 12, 17:30 UTC2h 5m
2026-07-12 SKW5254 - Jul 12, 01:35 UTCJul 12, 02:45 UTC1h 10m
2026-07-12 SKW5254 ORD → ASE Jul 12, 01:24 UTCJul 12, 03:55 UTC2h 31m
2026-07-11 SKW5956 - Jul 11, 19:10 UTCJul 11, 21:15 UTC2h 5m
2026-07-11 SKW5814 - Jul 11, 15:35 UTCJul 11, 17:20 UTC1h 45m
2026-07-11 SKW5259 - Jul 11, 12:30 UTCJul 11, 12:45 UTC15m
2026-07-11 SKW5259 SHV → IAH Jul 11, 12:37 UTCJul 11, 13:08 UTC31m
2026-07-11 SKW376Z DEN → SHV Jul 11, 01:50 UTCJul 11, 03:35 UTC1h 45m
2026-07-10 SKW5749 - Jul 10, 21:55 UTCJul 10, 22:30 UTC35m
2026-07-10 SKW5749 GUC → DEN Jul 10, 21:52 UTCJul 10, 22:26 UTC34m
2026-07-10 SKW342F - Jul 10, 19:40 UTCJul 10, 20:05 UTC25m
2026-07-10 SKW5787 - Jul 10, 16:20 UTCJul 10, 18:05 UTC1h 45m
2026-07-10 SKW5329 - Jul 10, 06:40 UTCJul 10, 07:20 UTC40m
2026-07-10 SKW5940 - Jul 10, 03:50 UTCJul 10, 05:20 UTC1h 30m
2026-07-10 SKW5940 ASE → LAX Jul 10, 03:40 UTCJul 10, 05:18 UTC1h 38m
2026-07-10 SKW5775 - Jul 10, 02:10 UTCJul 10, 02:25 UTC15m
2026-07-10 SKW5775 DEN → ASE Jul 10, 02:06 UTCJul 10, 02:38 UTC32m
2026-07-10 SKW5776 JAC → SFO Jul 10, 00:50 UTCJul 10, 01:15 UTC25m
2026-07-09 SKW5771 - Jul 9, 20:20 UTCJul 9, 20:50 UTC30m
2026-07-09 SKW5787 - Jul 9, 16:10 UTCJul 9, 17:55 UTC1h 45m
2026-07-09 SKW5329 - Jul 9, 05:20 UTCJul 9, 06:00 UTC40m
2026-07-09 SKW5940 - Jul 9, 02:50 UTCJul 9, 04:20 UTC1h 30m
2026-07-09 SKW5940 ASE → LAX Jul 9, 02:32 UTCJul 9, 04:25 UTC1h 53m
2026-07-09 SKW5775 - Jul 9, 01:00 UTCJul 9, 01:15 UTC15m
2026-07-08 SKW5776 JAC → SFO Jul 8, 23:35 UTCJul 9, 00:00 UTC25m
2026-07-08 SKW5771 - Jul 8, 19:55 UTCJul 8, 20:10 UTC15m
2026-07-08 SKW5771 DEN → ASE Jul 8, 20:00 UTCJul 8, 20:29 UTC29m
2026-07-08 SKW5772 - Jul 8, 17:50 UTCJul 8, 18:15 UTC25m
2026-07-08 SKW5711 - Jul 8, 00:25 UTCJul 8, 02:00 UTC1h 35m
2026-07-07 SKW5560 - Jul 7, 22:30 UTCJul 7, 23:05 UTC35m
2026-07-07 SKW5560 BIH → SFO Jul 7, 21:46 UTCJul 7, 23:04 UTC1h 18m
2026-07-07 SKW5854 - Jul 7, 20:15 UTCJul 7, 20:45 UTC30m
2026-07-07 SKW5745 - Jul 7, 17:10 UTCJul 7, 19:00 UTC1h 50m
2026-07-07 SKW5444 SFO → PHX Jul 7, 14:04 UTCJul 7, 14:28 UTC24m
2026-07-07 SKW5444 SFO → PHX Jul 7, 13:55 UTCJul 7, 14:10 UTC15m
2026-07-07 SKW5701 - Jul 7, 11:15 UTCJul 7, 12:25 UTC1h 10m
2026-07-07 SKW5701 FSD → DEN Jul 7, 11:24 UTCJul 7, 12:39 UTC1h 15m
2026-07-07 SKW309L - Jul 7, 03:40 UTCJul 7, 04:50 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 N638SY page for operator, model, and routing details .

Mode-S A85D1B frequently asked

What is Mode-S code A85D1B?
A85D1B is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N638SY.
Where is Mode-S A85D1B registered?
Mode-S code A85D1B 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 A85D1B broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A85D1B, octal 52056433, decimal 11,033,883.
What flights does A85D1B operate?
Mode-S A85D1B has broadcast 20 distinct callsigns, including SKW5329, SKW5787, SKW5779, SKW5775, SKW5940.