Apparatus

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sensors Mode-S transponder

A1A4C9

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N205CA · CESSNA 402 Businessliner · operated by HYANNIS AIR SERVICE INC DBA, CAPE AIR

Hex
A1A4C9
Octal
50322311
Decimal
10,593,481
Country
US
Tail
N205CA
Type
C402
No current signal · last broadcast 2d ago
Flights observed
219
Distinct callsigns
20
Country
US
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S A1A4C9.

Country allocation

The ICAO 24-bit address A1A4C9 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
KAP1903 - 26 2026-06-29
KAP65 - 24 2026-07-03
KAP161 - 18 2026-06-30
KAP6 Cape Air 16 2026-05-21
KAP189 Cape Air 16 2026-05-03
KAP91 Cape Air 14 2026-04-26
KAP131 Cape Air 12 2026-05-12
KAP713 Cape Air 11 2026-04-29
KAP635 Cape Air 10 2026-05-14
KAP323 Cape Air 10 2026-05-04
KAP87 Cape Air 7 2026-05-05
KAP47 - 7 2026-06-13
KAP222 - 7 2026-07-06
KAP202 Cape Air 7 2026-06-12
KAP627 Cape Air 5 2026-05-22
KAP157 Cape Air 4 2026-06-23
KAP98 Cape Air 3 2026-05-09
KAP876 Cape Air 3 2026-05-27
KAP55 Cape Air 3 2026-04-12
KAP350 Cape Air 3 2026-05-29

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-11 KAP63 NRR → SJU Jul 11, 19:40 UTCJul 11, 19:55 UTC15m
2026-07-06 KAP222 - Jul 6, 20:00 UTCJul 6, 20:15 UTC15m
2026-07-03 KAP65 - Jul 3, 22:05 UTCJul 3, 22:20 UTC15m
2026-07-03 KAP65 - Jul 3, 19:35 UTCJul 3, 19:55 UTC20m
2026-07-03 KAP65 - Jul 3, 17:45 UTCJul 3, 18:00 UTC15m
2026-07-03 KAP65 - Jul 3, 13:50 UTCJul 3, 14:05 UTC15m
2026-07-03 KAP65 - Jul 3, 11:30 UTCJul 3, 11:45 UTC15m
2026-07-02 KAP65 - Jul 2, 21:45 UTCJul 2, 22:05 UTC20m
2026-07-02 KAP65 - Jul 2, 19:30 UTCJul 2, 19:50 UTC20m
2026-07-02 KAP65 - Jul 2, 15:05 UTCJul 2, 15:50 UTC45m
2026-07-02 KAP65 - Jul 2, 13:50 UTCJul 2, 14:00 UTC10m
2026-07-02 KAP65 - Jul 2, 11:20 UTCJul 2, 11:35 UTC15m
2026-07-01 KAP65 CPX → SJU Jul 1, 21:40 UTCJul 1, 22:00 UTC20m
2026-07-01 KAP65 - Jul 1, 19:25 UTCJul 1, 19:45 UTC20m
2026-07-01 KAP80 - Jul 1, 18:25 UTCJul 1, 18:45 UTC20m
2026-07-01 KAP80 - Jul 1, 17:40 UTCJul 1, 17:55 UTC15m
2026-07-01 KAP505 BIL → SDY Jul 1, 15:25 UTCJul 1, 16:00 UTC35m
2026-07-01 KAP63 - Jul 1, 13:05 UTCJul 1, 13:45 UTC40m
2026-06-30 KAP333 - Jun 30, 17:10 UTCJun 30, 18:05 UTC55m
2026-06-30 KAP161 - Jun 30, 15:40 UTCJun 30, 15:50 UTC10m
2026-06-30 KAP161 - Jun 30, 14:45 UTCJun 30, 14:55 UTC10m
2026-06-30 KAP161 - Jun 30, 11:25 UTCJun 30, 11:35 UTC10m
2026-06-29 KAP1903 - Jun 29, 20:04 UTCJun 29, 20:19 UTC15m
2026-06-29 KAP1903 - Jun 29, 18:49 UTCJun 29, 19:00 UTC10m
2026-06-29 KAP1903 - Jun 29, 16:39 UTCJun 29, 16:55 UTC15m
2026-06-29 KAP1903 - Jun 29, 15:19 UTCJun 29, 15:30 UTC10m
2026-06-28 KAP1903 - Jun 28, 19:49 UTCJun 28, 20:09 UTC20m
2026-06-28 KAP1903 - Jun 28, 18:19 UTCJun 28, 18:34 UTC15m
2026-06-28 KAP1903 - Jun 28, 15:14 UTCJun 28, 15:34 UTC20m
2026-06-28 KAP1903 - Jun 28, 13:49 UTCJun 28, 13:59 UTC10m
2026-06-27 KAP1903 - Jun 27, 22:20 UTCJun 27, 22:29 UTC10m
2026-06-27 KAP1903 - Jun 27, 20:14 UTCJun 27, 20:34 UTC20m
2026-06-27 KAP1903 - Jun 27, 18:39 UTCJun 27, 18:49 UTC10m
2026-06-27 KAP1903 - Jun 27, 17:09 UTCJun 27, 17:25 UTC15m
2026-06-27 KAP1903 - Jun 27, 15:49 UTCJun 27, 16:00 UTC10m
2026-06-27 KAP1903 - Jun 27, 13:40 UTCJun 27, 14:00 UTC20m
2026-06-27 KAP1903 - Jun 27, 12:34 UTCJun 27, 12:50 UTC15m
2026-06-27 KAP1903 - Jun 27, 11:55 UTCJun 27, 12:04 UTC10m
2026-06-26 KAP1903 - Jun 26, 19:45 UTCJun 26, 20:00 UTC15m
2026-06-26 KAP1903 - Jun 26, 18:15 UTCJun 26, 18:34 UTC20m
2026-06-26 KAP1903 - Jun 26, 17:04 UTCJun 26, 17:35 UTC30m
2026-06-26 KAP1903 - Jun 26, 14:05 UTCJun 26, 14:15 UTC10m
2026-06-26 KAP1903 - Jun 26, 12:50 UTCJun 26, 13:04 UTC15m
2026-06-26 KAP1903 - Jun 26, 11:45 UTCJun 26, 12:00 UTC15m
2026-06-25 KAP161 - Jun 25, 21:40 UTCJun 25, 21:50 UTC10m
2026-06-25 KAP161 - Jun 25, 20:25 UTCJun 25, 20:39 UTC15m
2026-06-25 KAP161 - Jun 25, 18:55 UTCJun 25, 19:15 UTC20m
2026-06-25 KAP161 - Jun 25, 14:04 UTCJun 25, 14:14 UTC10m
2026-06-25 KAP161 - Jun 25, 12:30 UTCJun 25, 12:44 UTC15m
2026-06-23 KAP157 SJU → VQS Jun 23, 20:15 UTCJun 23, 20:24 UTC10m

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 N205CA page for operator, model, and routing details .

Mode-S A1A4C9 frequently asked

What is Mode-S code A1A4C9?
A1A4C9 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N205CA.
Where is Mode-S A1A4C9 registered?
Mode-S code A1A4C9 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 A1A4C9 broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex A1A4C9, octal 50322311, decimal 10,593,481.
What flights does A1A4C9 operate?
Mode-S A1A4C9 has broadcast 20 distinct callsigns, including KAP1903, KAP65, KAP161, KAP6, KAP189.