Apparatus

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sensors Mode-S transponder

A81815

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N620UX · EMBRAER ERJ-170-200 (long wing) · operated by UNITED AIRLINES INC

Hex
A81815
Octal
52014025
Decimal
11,016,213
Country
US
Tail
N620UX
Type
E75L
No current signal · last broadcast 19m ago
Flights observed
585
Distinct callsigns
20
Country
US
Last broadcast
19m ago

Last known position

Most recent position reported by Mode-S A81815.

Country allocation

The ICAO 24-bit address A81815 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
SKW5901 - 7 2026-06-18
SKW5645 SkyWest Airlines 7 2026-06-16
SKW5601 - 6 2026-06-19
SKW5290 - 6 2026-06-21
SKW5747 SkyWest Airlines 5 2026-06-16
SKW5577 - 5 2026-07-12
SKW5382 - 5 2026-06-15
SKW5256 SkyWest Airlines 5 2026-06-08
SKW4747 SkyWest Airlines 5 2026-05-06
SKW4703 SkyWest Airlines 5 2026-06-12
SKW4656 SkyWest Airlines 5 2026-06-19
SKW717C SkyWest Airlines 4 2026-06-03
SKW5936 - 4 2026-07-12
SKW5877 - 4 2026-04-13
SKW5857 SkyWest Airlines 4 2026-05-02
SKW5846 SkyWest Airlines 4 2026-06-09
SKW5797 SkyWest Airlines 4 2026-05-01
SKW5702 SkyWest Airlines 4 2026-06-12
SKW5644 - 4 2026-07-04
SKW5613 - 4 2026-06-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-15 SKW5542 - Jul 15, 14:55 UTCJul 15, 15:15 UTC20m
2026-07-15 SKW5461 - Jul 15, 04:30 UTCJul 15, 04:55 UTC25m
2026-07-15 SKW4722 - Jul 15, 02:10 UTCJul 15, 03:05 UTC55m
2026-07-14 SKW5457 - Jul 14, 23:50 UTCJul 15, 00:55 UTC1h 5m
2026-07-14 SKW5307 - Jul 14, 21:20 UTCJul 14, 22:00 UTC40m
2026-07-14 SKW5307 FAT → LAX Jul 14, 21:15 UTCJul 14, 21:59 UTC44m
2026-07-14 SKW5655 - Jul 14, 18:05 UTCJul 14, 20:05 UTC2h 0m
2026-07-14 SKW4710 DEN → DEN Jul 14, 00:30 UTCJul 14, 16:00 UTC15h 30m
2026-07-13 SKW5966 - Jul 13, 19:50 UTCJul 13, 21:55 UTC2h 5m
2026-07-13 SKW5966 ACV → DEN Jul 13, 19:43 UTCJul 13, 22:14 UTC2h 31m
2026-07-13 SKW4708 - Jul 13, 17:55 UTCJul 13, 18:25 UTC30m
2026-07-13 SKW4708 SFO → ACV Jul 13, 18:04 UTCJul 13, 18:37 UTC33m
2026-07-13 SKW5423 - Jul 13, 15:35 UTCJul 13, 17:05 UTC1h 30m
2026-07-13 SKW5986 - Jul 13, 02:05 UTCJul 13, 02:40 UTC35m
2026-07-12 SKW5936 - Jul 12, 22:45 UTCJul 13, 01:01 UTC2h 15m
2026-07-12 SKW5577 - Jul 12, 20:01 UTCJul 12, 21:30 UTC1h 30m
2026-07-12 SKW5577 SFO → FCA Jul 12, 19:42 UTCJul 12, 21:43 UTC2h 1m
2026-07-12 SKW5970 SLC → SFO Jul 12, 16:55 UTCJul 12, 18:40 UTC1h 45m
2026-07-12 SKW5970 SLC → SFO Jul 12, 16:48 UTCJul 12, 18:34 UTC1h 46m
2026-07-11 SKW5261 DEN → SLC Jul 11, 22:45 UTCJul 11, 23:50 UTC1h 5m
2026-07-11 SKW4686 - Jul 11, 18:50 UTCJul 11, 20:35 UTC1h 45m
2026-07-11 SKW5369 - Jul 11, 16:05 UTCJul 11, 17:30 UTC1h 25m
2026-07-11 SKW4660 - Jul 11, 13:05 UTCJul 11, 13:40 UTC35m
2026-07-11 SKW4660 HLN → DEN Jul 11, 12:45 UTCJul 11, 13:37 UTC52m
2026-07-11 SKW4705 DEN → HLN Jul 11, 02:29 UTCJul 11, 04:07 UTC1h 38m
2026-07-10 SKW4767 GUC → DEN Jul 10, 20:33 UTCJul 10, 20:50 UTC17m
2026-07-10 SKW5343 - Jul 10, 18:45 UTCJul 10, 19:10 UTC25m
2026-07-10 SKW5834 ABQ → DEN Jul 10, 16:55 UTCJul 10, 17:50 UTC55m
2026-07-10 SKW5487 DEN → ABQ Jul 10, 14:25 UTCJul 10, 15:25 UTC1h 0m
2026-07-10 SKW5355 - Jul 10, 11:20 UTCJul 10, 12:30 UTC1h 10m
2026-07-10 SKW4755 DEN → ICT Jul 10, 04:25 UTCJul 10, 05:35 UTC1h 10m
2026-07-10 SKW6032 - Jul 10, 01:25 UTCJul 10, 03:10 UTC1h 45m
2026-07-09 SKW5280 - Jul 9, 21:50 UTCJul 9, 23:05 UTC1h 15m
2026-07-09 SKW5812 - Jul 9, 18:50 UTCJul 9, 20:25 UTC1h 35m
2026-07-09 SKW5267 DEN → XNA Jul 9, 16:00 UTCJul 9, 17:20 UTC1h 20m
2026-07-09 SKW5602 - Jul 9, 13:35 UTCJul 9, 14:05 UTC30m
2026-07-09 SKW776V DEN → GUC Jul 9, 02:15 UTCJul 9, 02:45 UTC30m
2026-07-09 SKW776V DEN → GUC Jul 9, 02:16 UTCJul 9, 02:55 UTC39m
2026-07-08 SKW5630 - Jul 8, 23:40 UTCJul 9, 00:50 UTC1h 10m
2026-07-08 SKW5630 ICT → DEN Jul 8, 23:41 UTCJul 9, 00:47 UTC1h 6m
2026-07-08 SKW5454 DEN → ICT Jul 8, 20:25 UTCJul 8, 21:25 UTC1h 0m
2026-07-08 SKW716R DEN → DEN Jul 8, 13:55 UTCJul 8, 18:25 UTC4h 30m
2026-07-08 SKW5355 - Jul 8, 11:15 UTCJul 8, 12:20 UTC1h 5m
2026-07-08 SKW4755 DEN → ICT Jul 8, 03:45 UTCJul 8, 04:50 UTC1h 5m
2026-07-08 SKW4755 DEN → ICT Jul 8, 03:37 UTCJul 8, 04:48 UTC1h 11m
2026-07-08 SKW4652 ABQ → DEN Jul 8, 01:05 UTCJul 8, 02:10 UTC1h 5m
2026-07-07 SKW4760 DEN → ABQ Jul 7, 22:55 UTCJul 8, 00:05 UTC1h 10m
2026-07-07 SKW4658 - Jul 7, 20:00 UTCJul 7, 21:00 UTC1h 0m
2026-07-07 SKW4658 CPR → DEN Jul 7, 19:44 UTCJul 7, 20:43 UTC59m
2026-07-07 SKW771M - Jul 7, 17:50 UTCJul 7, 18:20 UTC30m

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 N620UX page for operator, model, and routing details .

Mode-S A81815 frequently asked

What is Mode-S code A81815?
A81815 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N620UX.
Where is Mode-S A81815 registered?
Mode-S code A81815 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 A81815 broadcasting right now?
No active broadcast right now. Last signal was 19m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A81815, octal 52014025, decimal 11,016,213.
What flights does A81815 operate?
Mode-S A81815 has broadcast 20 distinct callsigns, including SKW5901, SKW5645, SKW5601, SKW5290, SKW5747.