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sensors Mode-S transponder

AD237C

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N946AK · BOEING 737 MAX 9 · operated by ALASKA AIRLINES INC

Hex
AD237C
Octal
53221574
Decimal
11,346,812
Country
US
Tail
N946AK
Type
B39M
No current signal · last broadcast 3d ago
Flights observed
403
Distinct callsigns
20
Country
US
Last broadcast
3d ago

Last known position

Most recent position reported by Mode-S AD237C.

Country allocation

The ICAO 24-bit address AD237C 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
ASA95 Alaska Airlines 4 2026-06-09
ASA762 Alaska Airlines 4 2026-06-10
ASA541 Alaska Airlines 4 2026-07-01
ASA517 - 4 2026-07-08
ASA419 Alaska Airlines 4 2026-06-20
ASA416 - 4 2026-06-29
ASA300 Alaska Airlines 4 2026-06-20
ASA299 Alaska Airlines 4 2026-04-14
ASA266 Alaska Airlines 4 2026-06-04
ASA216 - 4 2026-07-05
ASA1477 Alaska Airlines 4 2026-05-29
ASA84 Alaska Airlines 3 2026-04-18
ASA787 Alaska Airlines 3 2026-05-30
ASA758 Alaska Airlines 3 2026-06-09
ASA745 Alaska Airlines 3 2026-05-16
ASA684 Alaska Airlines 3 2026-06-08
ASA657 Alaska Airlines 3 2026-05-16
ASA623 - 3 2026-06-29
ASA555 Alaska Airlines 3 2026-04-16
ASA54 - 3 2026-06-22

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-10 ASA9420 - Jul 10, 16:35 UTCJul 10, 20:15 UTC3h 40m
2026-07-10 ASA1498 ANC → SEA Jul 10, 09:05 UTCJul 10, 12:10 UTC3h 5m
2026-07-10 ASA667 SEA → ANC Jul 10, 03:45 UTCJul 10, 06:45 UTC3h 0m
2026-07-10 ASA667 SEA → ANC Jul 10, 03:42 UTCJul 10, 06:40 UTC2h 58m
2026-07-09 ASA508 - Jul 9, 21:15 UTCJul 10, 01:40 UTC4h 25m
2026-07-09 ASA508 SEA → CVG Jul 9, 16:05 UTCJul 9, 19:50 UTC3h 45m
2026-07-08 ASA517 PPM → SEA Jul 8, 23:10 UTCJul 9, 05:00 UTC5h 50m
2026-07-08 ASA516 SEA → FLL Jul 8, 16:35 UTCJul 8, 21:45 UTC5h 10m
2026-07-08 ASA563 - Jul 8, 11:20 UTCJul 8, 14:45 UTC3h 25m
2026-07-08 ASA564 SEA → MCI Jul 8, 01:55 UTCJul 8, 04:43 UTC2h 48m
2026-07-08 ASA564 - Jul 8, 01:50 UTCJul 8, 04:50 UTC3h 0m
2026-07-07 ASA315 ANC → SEA Jul 7, 17:20 UTCJul 7, 20:30 UTC3h 10m
2026-07-07 ASA1363 SEA → ANC Jul 7, 07:30 UTCJul 7, 10:20 UTC2h 50m
2026-07-07 ASA1363 SEA → ANC Jul 7, 07:27 UTCJul 7, 10:21 UTC2h 54m
2026-07-07 ASA544 PDX → SFO Jul 7, 01:30 UTCJul 7, 04:45 UTC3h 15m
2026-07-06 ASA659 LAX → SFO Jul 6, 20:55 UTCJul 6, 23:55 UTC3h 0m
2026-07-06 ASA1468 SMF → SEA Jul 6, 17:40 UTCJul 6, 19:05 UTC1h 25m
2026-07-06 ASA682 SEA → SMF Jul 6, 14:56 UTCJul 6, 16:05 UTC1h 9m
2026-07-06 ASA682 SEA → SMF Jul 6, 14:45 UTCJul 6, 16:10 UTC1h 25m
2026-07-06 ASA1509 FAI → SEA Jul 6, 09:50 UTCJul 6, 13:05 UTC3h 15m
2026-07-06 ASA1880 SEA → FAI Jul 6, 05:10 UTCJul 6, 08:15 UTC3h 5m
2026-07-05 ASA216 - Jul 5, 22:50 UTCJul 6, 03:30 UTC4h 40m
2026-07-05 ASA216 - Jul 5, 17:05 UTCJul 5, 20:55 UTC3h 50m
2026-07-04 ASA580 BUR → SEA Jul 4, 20:35 UTCJul 4, 22:35 UTC2h 0m
2026-07-04 ASA426 SEA → BUR Jul 4, 17:00 UTCJul 4, 19:05 UTC2h 5m
2026-07-04 ASA607 TPA → SFO Jul 4, 13:05 UTCJul 4, 15:25 UTC2h 20m
2026-07-04 ASA1332 - Jul 4, 03:30 UTCJul 4, 04:20 UTC50m
2026-07-03 ASA1332 - Jul 3, 23:25 UTCJul 3, 23:45 UTC20m
2026-07-03 ASA270 - Jul 3, 16:20 UTCJul 3, 22:00 UTC5h 40m
2026-07-03 ASA489 - Jul 3, 04:15 UTCJul 3, 06:20 UTC2h 5m
2026-07-02 ASA443 - Jul 2, 20:40 UTCJul 3, 01:55 UTC5h 15m
2026-07-02 ASA1776 PDX → PHL Jul 2, 14:34 UTCJul 2, 19:24 UTC4h 50m
2026-07-02 ASA1776 - Jul 2, 14:35 UTCJul 2, 19:20 UTC4h 45m
2026-07-02 ASA649 BUR → PDX Jul 2, 01:15 UTCJul 2, 03:05 UTC1h 50m
2026-07-02 ASA649 BUR → PDX Jul 2, 01:15 UTCJul 2, 03:05 UTC1h 50m
2026-07-01 ASA1386 PDX → BUR Jul 1, 22:00 UTCJul 1, 23:50 UTC1h 50m
2026-07-01 ASA1386 PDX → BUR Jul 1, 21:59 UTCJul 1, 23:47 UTC1h 48m
2026-07-01 ASA251 GEG → PDX Jul 1, 20:05 UTCJul 1, 20:55 UTC50m
2026-07-01 ASA250 PDX → GEG Jul 1, 17:50 UTCJul 1, 18:23 UTC33m
2026-07-01 ASA250 PDX → GEG Jul 1, 17:40 UTCJul 1, 18:30 UTC50m
2026-07-01 ASA541 AUS → PDX Jul 1, 12:35 UTCJul 1, 16:05 UTC3h 30m
2026-07-01 ASA372 SEA → DFW Jul 1, 01:45 UTCJul 1, 05:25 UTC3h 40m
2026-06-30 ASA405 SEA → OKC Jun 30, 20:10 UTCJun 30, 23:30 UTC3h 20m
2026-06-30 ASA405 SEA → OKC Jun 30, 15:40 UTCJun 30, 18:55 UTC3h 15m
2026-06-30 ASA647 - Jun 30, 01:04 UTCJun 30, 04:50 UTC3h 46m
2026-06-29 ASA647 SEA → STL Jun 29, 20:15 UTCJun 29, 23:34 UTC3h 20m
2026-06-29 ASA623 - Jun 29, 14:39 UTCJun 29, 18:55 UTC4h 15m
2026-06-29 ASA416 SEA → BNA Jun 29, 00:44 UTCJun 29, 04:39 UTC3h 55m
2026-06-29 ASA416 SEA → BNA Jun 29, 00:42 UTCJun 29, 04:41 UTC3h 59m
2026-06-28 ASA1305 LAX → SEA Jun 28, 20:57 UTCJun 28, 22:54 UTC1h 57m

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 N946AK page for operator, model, and routing details .

Mode-S AD237C frequently asked

What is Mode-S code AD237C?
AD237C is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N946AK.
Where is Mode-S AD237C registered?
Mode-S code AD237C 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 AD237C broadcasting right now?
No active broadcast right now. Last signal was 3d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AD237C, octal 53221574, decimal 11,346,812.
What flights does AD237C operate?
Mode-S AD237C has broadcast 20 distinct callsigns, including ASA95, ASA762, ASA541, ASA517, ASA419.