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sensors Mode-S transponder

A959DF

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N701SK · BOMBARDIER Regional Jet CRJ-700 · operated by SKYWEST AIRLINES INC

Hex
A959DF
Octal
52254737
Decimal
11,098,591
Country
US
Tail
N701SK
Type
CRJ7
Broadcasting now · callsign SKW4893 · 15,675 ft
Flights observed
332
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:45 UTC

Current position

A959DF is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address A959DF 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
SKW6380 - 10 2026-06-30
SKW6399 - 8 2026-07-15
SKW6440 SkyWest Airlines 7 2026-06-15
SKW6324 SkyWest Airlines 7 2026-05-29
SKW6442 SkyWest Airlines 6 2026-04-17
SKW4999 SkyWest Airlines 6 2026-07-21
SKW4936 SkyWest Airlines 6 2026-07-22
SKW9908 - 5 2026-07-06
SKW6454 SkyWest Airlines 5 2026-05-19
SKW5013 SkyWest Airlines 5 2026-04-26
SKW6456 SkyWest Airlines 4 2026-05-09
SKW6405 SkyWest Airlines 4 2026-07-22
SKW6384 SkyWest Airlines 4 2026-06-13
SKW6245 - 4 2026-07-13
SKW6195 - 4 2026-07-17
SKW6193 - 4 2026-06-20
SKW5012 SkyWest Airlines 4 2026-05-30
SKW4984 SkyWest Airlines 4 2026-05-17
SKW4949 SkyWest Airlines 4 2026-07-25
SKW4885 - 4 2026-07-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 SKW4891 LAX → PDX Jul 26, 21:20 UTCJul 26, 21:45 UTC25m
2026-07-26 SKW6473 ICT → PHX Jul 26, 18:20 UTCJul 26, 20:10 UTC1h 50m
2026-07-26 SKW6363 DFW → BRO Jul 26, 13:40 UTCJul 26, 14:35 UTC55m
2026-07-26 SKW6363 DFW → BRO Jul 26, 13:47 UTCJul 26, 14:41 UTC54m
2026-07-26 SKW6363 DFW → BRO Jul 26, 11:55 UTCJul 26, 12:45 UTC50m
2026-07-26 SKW6433 PHX → BFL Jul 26, 00:30 UTCJul 26, 02:30 UTC2h 0m
2026-07-25 SKW6433 PHX → BFL Jul 25, 22:20 UTCJul 25, 23:50 UTC1h 30m
2026-07-25 SKW4949 ORD → PIA Jul 25, 18:45 UTCJul 25, 19:45 UTC1h 0m
2026-07-25 SKW4949 ORD → PIA Jul 25, 16:50 UTCJul 25, 17:40 UTC50m
2026-07-23 SKW6344 PHX → SJC Jul 23, 22:45 UTCJul 23, 23:10 UTC25m
2026-07-23 SKW6446 PHX → ELP Jul 23, 19:50 UTCJul 23, 21:10 UTC1h 20m
2026-07-23 SKW4938 - Jul 23, 02:55 UTCJul 23, 15:15 UTC12h 20m
2026-07-23 SKW6436 DFW → SAF Jul 23, 02:40 UTCJul 23, 02:50 UTC10m
2026-07-22 SKW4936 MSY → DFW Jul 22, 18:55 UTCJul 22, 19:35 UTC40m
2026-07-22 SKW6405 DFW → SAF Jul 22, 00:05 UTCJul 22, 01:05 UTC1h 0m
2026-07-21 SKW4936 MSY → DFW Jul 21, 21:10 UTCJul 21, 21:55 UTC45m
2026-07-21 SKW6343 DAY → ORD Jul 21, 15:30 UTCJul 21, 15:45 UTC15m
2026-07-21 SKW6343 DAY → ORD Jul 21, 15:23 UTCJul 21, 16:03 UTC40m
2026-07-21 SKW6343 DAY → ORD Jul 21, 13:45 UTCJul 21, 14:25 UTC40m
2026-07-21 SKW4999 BPT → DFW Jul 21, 04:05 UTCJul 21, 04:25 UTC20m
2026-07-21 SKW4999 BPT → DFW Jul 21, 04:01 UTCJul 21, 04:30 UTC29m
2026-07-20 SKW4956 DFW → SJT Jul 20, 22:25 UTCJul 20, 23:50 UTC1h 25m
2026-07-20 SKW4936 MSY → DFW Jul 20, 18:35 UTCJul 20, 19:20 UTC45m
2026-07-20 SKW6329 - Jul 20, 11:15 UTCJul 20, 11:45 UTC30m
2026-07-20 SKW6329 BPT → DFW Jul 20, 11:11 UTCJul 20, 12:04 UTC53m
2026-07-20 SKW4956 DFW → SJT Jul 20, 00:25 UTCJul 20, 01:55 UTC1h 30m
2026-07-19 SKW4956 DFW → SJT Jul 19, 20:50 UTCJul 19, 22:15 UTC1h 25m
2026-07-18 SKW5006 ORD → TVC Jul 18, 21:40 UTCJul 18, 22:30 UTC50m
2026-07-18 SKW5006 ORD → TVC Jul 18, 19:50 UTCJul 18, 20:45 UTC55m
2026-07-18 SKW6296 - Jul 18, 13:55 UTCJul 18, 14:50 UTC55m
2026-07-18 SKW4923 DSM → ORD Jul 18, 01:10 UTCJul 18, 01:54 UTC45m
2026-07-17 SKW5002 - Jul 17, 19:40 UTCJul 17, 20:25 UTC45m
2026-07-17 SKW4963 - Jul 17, 13:55 UTCJul 17, 15:20 UTC1h 25m
2026-07-17 SKW6195 - Jul 17, 11:20 UTCJul 17, 11:50 UTC30m
2026-07-17 SKW4999 BPT → DFW Jul 17, 05:20 UTCJul 17, 05:39 UTC20m
2026-07-17 SKW4999 BPT → DFW Jul 17, 05:17 UTCJul 17, 05:44 UTC27m
2026-07-17 SKW6342 - Jul 17, 02:54 UTCJul 17, 04:10 UTC1h 15m
2026-07-16 SKW4936 - Jul 16, 20:39 UTCJul 16, 21:30 UTC50m
2026-07-16 SKW4930 - Jul 16, 10:15 UTCJul 16, 10:55 UTC40m
2026-07-16 SKW4885 - Jul 16, 05:50 UTCJul 16, 06:25 UTC35m
2026-07-15 SKW6410 AUS → DFW Jul 15, 23:30 UTCJul 16, 00:15 UTC45m
2026-07-15 SKW6427 - Jul 15, 16:30 UTCJul 15, 18:25 UTC1h 55m
2026-07-15 SKW6427 ORD → ASE Jul 15, 16:31 UTCJul 15, 18:34 UTC2h 3m
2026-07-15 SKW6399 - Jul 15, 02:45 UTCJul 15, 03:45 UTC1h 0m
2026-07-15 SKW6399 - Jul 15, 00:55 UTCJul 15, 01:50 UTC55m
2026-07-14 SKW4903 - Jul 14, 20:40 UTCJul 14, 21:25 UTC45m
2026-07-14 SKW4914 - Jul 14, 11:30 UTCJul 14, 12:10 UTC40m
2026-07-14 SKW4914 MKE → ORD Jul 14, 11:29 UTCJul 14, 11:55 UTC26m
2026-07-14 SKW6357 - Jul 14, 02:40 UTCJul 14, 02:55 UTC15m
2026-07-13 SKW6245 - Jul 13, 23:30 UTCJul 14, 00:30 UTC1h 0m

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 N701SK page for operator, model, and routing details .

Mode-S A959DF frequently asked

What is Mode-S code A959DF?
A959DF is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N701SK.
Where is Mode-S A959DF registered?
Mode-S code A959DF 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 A959DF broadcasting right now?
Yes. Mode-S A959DF is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A959DF, octal 52254737, decimal 11,098,591.
What flights does A959DF operate?
Mode-S A959DF has broadcast 20 distinct callsigns, including SKW6380, SKW6399, SKW6440, SKW6324, SKW6442.