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sensors Mode-S transponder

AB3CD4

ICAO 24-bit transponder address · allocated to United States

Currently assigned to N823JM · AIRBUS HELICOPTERS EC-135/635 · operated by MASSACHUSETTS STATE POLICE

Hex
AB3CD4
Octal
52636324
Decimal
11,222,228
Country
US
Tail
N823JM
Type
EC35
No current signal · last broadcast 1d ago
Flights observed
128
Distinct callsigns
1
Country
US
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S AB3CD4.

Country allocation

The ICAO 24-bit address AB3CD4 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 1 distinct

Callsign Airline Flights Last seen
N823JM - 128 2026-07-13

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-13 N823JM - Jul 13, 01:55 UTCJul 13, 03:45 UTC1h 50m
2026-07-12 N823JM - Jul 12, 21:30 UTCJul 12, 23:20 UTC1h 50m
2026-07-11 N823JM - Jul 11, 18:00 UTCJul 11, 19:25 UTC1h 25m
2026-07-11 N823JM - Jul 11, 14:45 UTCJul 11, 16:15 UTC1h 30m
2026-07-11 N823JM - Jul 11, 12:35 UTCJul 11, 13:40 UTC1h 5m
2026-07-11 N823JM - Jul 11, 12:00 UTCJul 11, 12:20 UTC20m
2026-07-11 N823JM PYM → PYM Jul 11, 08:01 UTCJul 11, 09:30 UTC1h 30m
2026-07-10 N823JM - Jul 10, 21:00 UTCJul 10, 21:50 UTC50m
2026-07-10 N823JM - Jul 10, 14:40 UTCJul 10, 16:35 UTC1h 55m
2026-07-09 N823JM - Jul 9, 22:00 UTCJul 9, 23:15 UTC1h 15m
2026-07-09 N823JM - Jul 9, 18:25 UTCJul 9, 19:35 UTC1h 10m
2026-07-09 N823JM - Jul 9, 16:10 UTCJul 9, 17:35 UTC1h 25m
2026-07-08 N823JM ORH → PYM Jul 8, 21:15 UTCJul 8, 23:00 UTC1h 45m
2026-07-08 N823JM - Jul 8, 18:40 UTCJul 8, 20:10 UTC1h 30m
2026-07-08 N823JM - Jul 8, 16:50 UTCJul 8, 17:05 UTC15m
2026-07-08 N823JM - Jul 8, 15:05 UTCJul 8, 16:00 UTC55m
2026-07-08 N823JM - Jul 8, 13:05 UTCJul 8, 13:30 UTC25m
2026-07-05 N823JM - Jul 5, 06:05 UTCJul 5, 07:30 UTC1h 25m
2026-07-04 N823JM - Jul 4, 23:45 UTCJul 5, 01:05 UTC1h 20m
2026-07-04 N823JM - Jul 4, 20:05 UTCJul 4, 22:15 UTC2h 10m
2026-07-04 N823JM - Jul 4, 14:25 UTCJul 4, 16:40 UTC2h 15m
2026-07-04 N823JM - Jul 4, 04:55 UTCJul 4, 05:55 UTC1h 0m
2026-07-04 N823JM - Jul 4, 02:25 UTCJul 4, 04:20 UTC1h 55m
2026-07-04 N823JM - Jul 4, 00:05 UTCJul 4, 01:45 UTC1h 40m
2026-07-03 N823JM - Jul 3, 15:25 UTCJul 3, 16:50 UTC1h 25m
2026-07-02 N823JM - Jul 2, 19:05 UTCJul 2, 19:50 UTC45m
2026-07-02 N823JM - Jul 2, 16:10 UTCJul 2, 17:05 UTC55m
2026-06-29 N823JM - Jun 29, 18:30 UTCJun 29, 20:15 UTC1h 45m
2026-06-29 N823JM - Jun 29, 15:24 UTCJun 29, 16:39 UTC1h 15m
2026-06-29 N823JM - Jun 29, 00:20 UTCJun 29, 01:05 UTC45m
2026-06-28 N823JM - Jun 28, 20:50 UTCJun 28, 21:59 UTC1h 10m
2026-06-28 N823JM - Jun 28, 17:44 UTCJun 28, 18:00 UTC15m
2026-06-28 N823JM - Jun 28, 16:39 UTCJun 28, 17:00 UTC20m
2026-06-28 N823JM - Jun 28, 15:40 UTCJun 28, 16:00 UTC20m
2026-06-27 N823JM - Jun 27, 04:44 UTCJun 27, 05:35 UTC50m
2026-06-27 N823JM - Jun 27, 01:49 UTCJun 27, 02:55 UTC1h 5m
2026-06-26 N823JM - Jun 26, 20:29 UTCJun 26, 21:20 UTC50m
2026-06-26 N823JM - Jun 26, 06:19 UTCJun 26, 07:35 UTC1h 15m
2026-06-25 N823JM - Jun 25, 22:45 UTCJun 25, 23:44 UTC1h 0m
2026-06-25 N823JM - Jun 25, 18:45 UTCJun 25, 21:59 UTC3h 15m
2026-06-25 N823JM - Jun 25, 14:50 UTCJun 25, 16:09 UTC1h 20m
2026-06-23 N823JM - Jun 23, 23:00 UTCJun 24, 00:15 UTC1h 15m
2026-06-22 N823JM - Jun 22, 14:59 UTCJun 22, 15:45 UTC45m
2026-06-22 N823JM - Jun 22, 13:54 UTCJun 22, 14:14 UTC20m
2026-06-21 N823JM - Jun 21, 21:34 UTCJun 21, 23:00 UTC1h 25m
2026-06-21 N823JM - Jun 21, 16:34 UTCJun 21, 16:59 UTC25m
2026-06-20 N823JM - Jun 20, 15:24 UTCJun 20, 16:00 UTC35m
2026-06-20 N823JM - Jun 20, 13:14 UTCJun 20, 13:59 UTC45m
2026-06-19 N823JM - Jun 19, 23:19 UTCJun 20, 01:29 UTC2h 10m
2026-06-19 N823JM - Jun 19, 19:49 UTCJun 19, 21:49 UTC2h 0m

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 N823JM page for operator, model, and routing details .

Mode-S AB3CD4 frequently asked

What is Mode-S code AB3CD4?
AB3CD4 is an ICAO 24-bit transponder address. Allocated to United States. Assigned to N823JM.
Where is Mode-S AB3CD4 registered?
Mode-S code AB3CD4 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 AB3CD4 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex AB3CD4, octal 52636324, decimal 11,222,228.
What flights does AB3CD4 operate?
Mode-S AB3CD4 has broadcast 1 distinct callsign, including N823JM.