sensors Mode-S transponder

A9873D

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N713AL · BOEING 737 MAX 9 · operated by ALASKA AIRLINES INC

Hex
A9873D
Octal
52303475
Decimal
11,110,205
Country
US
Tail
N713AL
Type
B39M
No current signal · last broadcast 1h ago
Flights observed
139
Distinct callsigns
20
Country
US
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S A9873D.

Country allocation

The ICAO 24-bit address A9873D 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
ASA211 Alaska Airlines 5 2026-05-23
ASA771 Alaska Airlines 4 2026-04-15
ASA41 Alaska Airlines 4 2026-05-23
ASA395 Alaska Airlines 4 2026-04-15
ASA1406 Alaska Airlines 4 2026-05-23
ASA781 Alaska Airlines 3 2026-05-11
ASA648 Alaska Airlines 3 2026-04-15
ASA414 - 3 2026-04-14
ASA369 - 3 2026-04-13
ASA272 Alaska Airlines 3 2026-05-11
ASA17 Alaska Airlines 3 2026-05-08
ASA1491 Alaska Airlines 3 2026-05-10
ASA81 Alaska Airlines 2 2026-05-21
ASA787 Alaska Airlines 2 2026-05-12
ASA737 Alaska Airlines 2 2026-05-04
ASA641 Alaska Airlines 2 2026-04-16
ASA626 Alaska Airlines 2 2026-05-30
ASA604 - 2 2026-04-16
ASA592 Alaska Airlines 2 2026-05-14
ASA565 Alaska Airlines 2 2026-05-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 ASA626 SFO → SEA May 30, 00:05 UTCMay 30, 00:25 UTC20m
2026-05-29 ASA626 SFO → SEA May 29, 18:35 UTCMay 29, 19:35 UTC1h 0m
2026-05-29 ASA479 JFK → SFO May 29, 14:30 UTCMay 29, 16:40 UTC2h 10m
2026-05-29 ASA56 LAX → PDX May 29, 07:35 UTCMay 29, 12:25 UTC4h 50m
2026-05-29 ASA53 EWR → PDX May 29, 00:50 UTCMay 29, 05:25 UTC4h 35m
2026-05-28 ASA658 SEA → PHX May 28, 21:15 UTCMay 28, 23:20 UTC2h 5m
2026-05-28 ASA329 ORD → SEA May 28, 15:30 UTCMay 28, 19:05 UTC3h 35m
2026-05-28 ASA437 CMH → SEA May 28, 07:35 UTCMay 28, 13:20 UTC5h 45m
2026-05-28 ASA437 CMH → SEA May 28, 07:25 UTCMay 28, 12:58 UTC5h 33m
2026-05-28 ASA425 SFO → BOS May 28, 03:30 UTCMay 28, 04:40 UTC1h 10m
2026-05-28 ASA425 SFO → BOS May 28, 03:39 UTCMay 28, 04:47 UTC1h 8m
2026-05-28 ASA617 SEA → OAK May 28, 00:35 UTCMay 28, 01:50 UTC1h 15m
2026-05-27 ASA1412 SJD → SEA May 27, 22:40 UTCMay 27, 23:25 UTC45m
2026-05-27 ASA1485 BOS → SAN May 27, 20:45 UTCMay 27, 21:35 UTC50m
2026-05-27 ASA519 FLL → SEA May 27, 14:30 UTCMay 27, 19:25 UTC4h 55m
2026-05-27 ASA752 SEA → PSP May 27, 07:40 UTCMay 27, 12:35 UTC4h 55m
2026-05-27 ASA1455 PDX → SJC May 27, 01:14 UTCMay 27, 04:34 UTC3h 20m
2026-05-26 ASA325 ORD → PDX May 26, 20:00 UTCMay 26, 23:39 UTC3h 40m
2026-05-26 ASA324 SEA → SJC May 26, 14:40 UTCMay 26, 18:24 UTC3h 45m
2026-05-25 ASA1421 SNA → SEA May 25, 23:14 UTCMay 26, 03:05 UTC3h 50m
2026-05-25 ASA438 SEA → IAH May 25, 18:00 UTCMay 25, 22:05 UTC4h 5m
2026-05-25 ASA1380 PDX → CUN May 25, 12:05 UTCMay 25, 15:55 UTC3h 50m
2026-05-25 ASA1380 PDX → CUN May 25, 12:02 UTCMay 25, 15:39 UTC3h 37m
2026-05-25 ASA1381 CUN → PDX May 25, 01:55 UTCMay 25, 04:50 UTC2h 55m
2026-05-24 ASA565 LAX → PDX May 24, 23:00 UTCMay 24, 23:35 UTC35m
2026-05-24 ASA565 LAX → PDX May 24, 19:00 UTCMay 24, 20:30 UTC1h 30m
2026-05-24 ASA299 EWR → SEA May 24, 11:50 UTCMay 24, 17:10 UTC5h 20m
2026-05-24 ASA372 SEA → DFW May 24, 05:05 UTCMay 24, 10:00 UTC4h 55m
2026-05-23 ASA41 MCO → SFO May 23, 20:45 UTCMay 24, 02:25 UTC5h 40m
2026-05-23 ASA211 CUN → SEA May 23, 18:50 UTCMay 23, 18:55 UTC5m
2026-05-23 ASA211 CUN → SEA May 23, 13:44 UTCMay 23, 18:31 UTC4h 47m
2026-05-23 ASA211 CUN → SEA May 23, 13:45 UTCMay 23, 18:55 UTC5h 10m
2026-05-23 ASA1406 LAX → ZLO May 23, 04:21 UTCMay 23, 05:24 UTC1h 3m
2026-05-23 ASA1406 LAX → ZLO May 23, 04:25 UTCMay 23, 05:30 UTC1h 5m
2026-05-22 ASA297 SAN → EWR May 22, 21:45 UTCMay 23, 03:00 UTC5h 14m
2026-05-22 ASA286 LAX → EWR May 22, 14:55 UTCMay 22, 19:40 UTC4h 45m
2026-05-22 ASA513 SNA → SEA May 22, 04:10 UTCMay 22, 05:00 UTC50m
2026-05-21 ASA81 ANC → ORD May 21, 17:30 UTCMay 21, 18:10 UTC40m
2026-05-21 ASA81 ANC → ORD May 21, 17:29 UTCMay 21, 22:21 UTC4h 52m
2026-05-21 ASA1351 SJC → SEA May 21, 08:20 UTCMay 21, 08:45 UTC25m
2026-05-21 ASA1351 SJC → SEA May 21, 08:11 UTCMay 21, 13:24 UTC5h 13m
2026-05-21 ASA1352 SFO → BOS May 21, 00:00 UTCMay 21, 04:25 UTC4h 25m
2026-05-20 ASA1352 SFO → BOS May 20, 23:57 UTCMay 21, 05:09 UTC5h 12m
2026-05-20 ASA212 SEA → SJC May 20, 21:30 UTCMay 20, 22:25 UTC55m
2026-05-20 ASA227 SJC → SEA May 20, 13:55 UTCMay 20, 19:50 UTC5h 55m
2026-05-20 ASA486 SEA → IAD May 20, 06:05 UTCMay 20, 11:05 UTC5h 0m
2026-05-19 ASA41 MCO → SFO May 19, 20:55 UTCMay 20, 02:45 UTC5h 50m
2026-05-19 ASA211 CUN → SEA May 19, 13:25 UTCMay 19, 18:25 UTC5h 0m
2026-05-18 ASA41 MCO → SFO May 18, 20:30 UTCMay 19, 02:25 UTC5h 55m
2026-05-18 ASA41 MCO → SFO May 18, 20:27 UTCMay 19, 02:18 UTC5h 51m

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 N713AL page for operator, model, and routing details .

Mode-S A9873D frequently asked

What is Mode-S code A9873D?
A9873D is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N713AL.
Where is Mode-S A9873D registered?
Mode-S code A9873D 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 A9873D 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 A9873D, octal 52303475, decimal 11,110,205.
What flights does A9873D operate?
Mode-S A9873D has broadcast 20 distinct callsigns, including ASA211, ASA771, ASA41, ASA395, ASA1406.