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sensors Mode-S transponder

A56866

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N448AS · BOEING 737-900 · operated by ALASKA AIRLINES INC

Hex
A56866
Octal
51264146
Decimal
10,840,166
Country
US
Tail
N448AS
Type
B739
No current signal · last broadcast Jul 26, 21:25 UTC
Flights observed
432
Distinct callsigns
20
Country
US
Last broadcast
Jul 26, 21:25 UTC

Last known position

Most recent position reported by Mode-S A56866.

Country allocation

The ICAO 24-bit address A56866 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
ASA17 Alaska Airlines 8 2026-05-28
ASA41 Alaska Airlines 7 2026-07-26
ASA20 Alaska Airlines 7 2026-06-10
ASA389 Alaska Airlines 5 2026-06-11
ASA204 Alaska Airlines 5 2026-07-17
ASA1420 - 5 2026-07-22
ASA771 Alaska Airlines 4 2026-04-16
ASA520 Alaska Airlines 4 2026-04-26
ASA24 Alaska Airlines 4 2026-04-15
ASA227 Alaska Airlines 4 2026-06-02
ASA211 Alaska Airlines 4 2026-07-26
ASA1394 - 4 2026-06-16
ASA1366 Alaska Airlines 4 2026-06-08
ASA777 Alaska Airlines 3 2026-05-14
ASA633 Alaska Airlines 3 2026-07-20
ASA565 Alaska Airlines 3 2026-05-29
ASA564 Alaska Airlines 3 2026-07-23
ASA558 - 3 2026-07-10
ASA515 - 3 2026-07-10
ASA514 - 3 2026-07-10

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ASA41 MCO → SFO Jul 26, 16:00 UTCJul 26, 21:25 UTC5h 25m
2026-07-26 ASA211 CUN → SEA Jul 26, 05:00 UTCJul 26, 10:10 UTC5h 11m
2026-07-26 ASA1379 SFO → PVR Jul 26, 00:25 UTCJul 26, 02:25 UTC2h 0m
2026-07-25 ASA1379 SFO → PVR Jul 25, 23:47 UTCJul 26, 02:16 UTC2h 29m
2026-07-25 ASA421 PDX → SFO Jul 25, 18:48 UTCJul 25, 22:30 UTC3h 42m
2026-07-25 ASA421 PDX → SFO Jul 25, 18:35 UTCJul 25, 21:40 UTC3h 5m
2026-07-25 ASA748 SFO → LAS Jul 25, 14:30 UTCJul 25, 16:30 UTC2h 0m
2026-07-25 ASA748 SFO → LAS Jul 25, 14:26 UTCJul 25, 16:20 UTC1h 54m
2026-07-25 ASA617 SEA → OAK Jul 25, 00:45 UTCJul 25, 05:46 UTC5h 1m
2026-07-24 ASA1330 LAX → LIR Jul 24, 17:50 UTCJul 25, 05:30 UTC11h 40m
2026-07-24 ASA1620 SEA → LAX Jul 24, 13:25 UTCJul 24, 14:20 UTC55m
2026-07-24 ASA590 SFO → ORD Jul 24, 05:45 UTCJul 24, 07:30 UTC1h 45m
2026-07-23 ASA450 CMH → SEA Jul 23, 22:45 UTCJul 24, 03:20 UTC4h 35m
2026-07-23 ASA450 CMH → SEA Jul 23, 17:30 UTCJul 23, 21:10 UTC3h 40m
2026-07-23 ASA563 MCI → SEA Jul 23, 12:10 UTCJul 23, 15:35 UTC3h 25m
2026-07-23 ASA564 SEA → MCI Jul 23, 02:40 UTCJul 23, 05:30 UTC2h 50m
2026-07-22 ASA439 SEA → SFO Jul 22, 20:05 UTCJul 23, 00:15 UTC4h 10m
2026-07-22 ASA1420 - Jul 22, 14:20 UTCJul 22, 18:15 UTC3h 55m
2026-07-21 ASA1350 SEA → SFO Jul 21, 21:50 UTCJul 22, 02:10 UTC4h 20m
2026-07-21 ASA1345 SEA → BNA Jul 21, 16:35 UTCJul 21, 20:15 UTC3h 40m
2026-07-21 ASA387 MSP → SEA Jul 21, 11:05 UTCJul 21, 14:25 UTC3h 20m
2026-07-21 ASA386 SEA → MSP Jul 21, 02:10 UTCJul 21, 04:45 UTC2h 35m
2026-07-20 ASA652 - Jul 20, 22:20 UTCJul 21, 00:10 UTC1h 49m
2026-07-20 ASA633 SAN → SEA Jul 20, 19:20 UTCJul 20, 21:00 UTC1h 40m
2026-07-20 ASA299 EWR → SEA Jul 20, 11:35 UTCJul 20, 17:15 UTC5h 40m
2026-07-20 ASA1631 SFO → EWR Jul 20, 04:55 UTCJul 20, 09:20 UTC4h 25m
2026-07-20 ASA662 PHX → PDX Jul 20, 01:10 UTCJul 20, 03:15 UTC2h 5m
2026-07-19 ASA700 SEA → PHX Jul 19, 21:10 UTCJul 19, 23:45 UTC2h 35m
2026-07-19 ASA1311 SEA → SFO Jul 19, 17:25 UTCJul 19, 18:50 UTC1h 25m
2026-07-19 ASA1311 SEA → SFO Jul 19, 17:22 UTCJul 19, 18:48 UTC1h 26m
2026-07-19 ASA1448 SEA → SJC Jul 19, 14:20 UTCJul 19, 16:10 UTC1h 50m
2026-07-18 ASA572 RDU → SEA Jul 18, 22:40 UTCJul 19, 03:40 UTC5h 0m
2026-07-18 ASA572 RDU → SEA Jul 18, 15:50 UTCJul 18, 20:35 UTC4h 45m
2026-07-18 ASA499 PDX → SEA Jul 18, 13:30 UTCJul 18, 14:00 UTC30m
2026-07-18 ASA650 - Jul 18, 05:05 UTCJul 18, 07:20 UTC2h 15m
2026-07-18 ASA744 SEA → PHX Jul 18, 00:55 UTCJul 18, 03:50 UTC2h 56m
2026-07-17 ASA790 - Jul 17, 22:00 UTCJul 17, 23:30 UTC1h 30m
2026-07-17 ASA790 SFO → SEA Jul 17, 21:47 UTCJul 17, 23:11 UTC1h 24m
2026-07-17 ASA570 LAS → SFO Jul 17, 18:05 UTCJul 17, 19:09 UTC1h 5m
2026-07-17 ASA718 - Jul 17, 14:39 UTCJul 17, 15:49 UTC1h 10m
2026-07-17 ASA718 SFO → LAS Jul 17, 14:47 UTCJul 17, 15:48 UTC1h 1m
2026-07-17 ASA404 - Jul 17, 08:20 UTCJul 17, 09:04 UTC45m
2026-07-17 ASA404 - Jul 17, 04:29 UTCJul 17, 04:39 UTC10m
2026-07-17 ASA404 KOA → SFO Jul 17, 04:29 UTCJul 17, 08:56 UTC4h 27m
2026-07-17 ASA204 LAX → SFO Jul 17, 02:54 UTCJul 17, 03:14 UTC20m
2026-07-16 ASA204 LAX → SFO Jul 16, 21:45 UTCJul 16, 22:40 UTC55m
2026-07-16 ASA204 LAX → SFO Jul 16, 20:48 UTCJul 17, 03:07 UTC6h 19m
2026-07-16 ASA78 - Jul 16, 12:34 UTCJul 16, 17:10 UTC4h 35m
2026-07-16 ASA77 - Jul 16, 06:45 UTCJul 16, 10:50 UTC4h 5m
2026-07-15 ASA419 MCO → SEA Jul 15, 21:10 UTCJul 16, 02:25 UTC5h 15m

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 N448AS page for operator, model, and routing details .

Mode-S A56866 frequently asked

What is Mode-S code A56866?
A56866 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N448AS.
Where is Mode-S A56866 registered?
Mode-S code A56866 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 A56866 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:25 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A56866, octal 51264146, decimal 10,840,166.
What flights does A56866 operate?
Mode-S A56866 has broadcast 20 distinct callsigns, including ASA17, ASA41, ASA20, ASA389, ASA204.