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sensors Mode-S transponder

4D4020

ICAO 24-bit transponder address · allocated to Monaco

Currently assigned to 3A-MAX · AEROSPATIALE AS-350 Ecureuil

Hex
4D4020
Octal
23240040
Decimal
5,062,688
Country
MC
Tail
3A-MAX
Type
AS50
No current signal · last broadcast 15h ago
Flights observed
306
Distinct callsigns
1
Country
MC
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S 4D4020.

Country allocation

The ICAO 24-bit address 4D4020 falls within the block assigned to Monaco (MC) by ICAO Annex 10, Volume III. Every aircraft registered in Monaco 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
3AMAX - 306 2026-07-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 3AMAX CEQ → CEQ Jul 14, 12:00 UTCJul 14, 13:05 UTC1h 5m
2026-07-14 3AMAX CEQ → CEQ Jul 14, 10:05 UTCJul 14, 10:20 UTC15m
2026-06-15 3AMAX NCE → CEQ Jun 15, 12:30 UTCJun 15, 13:00 UTC30m
2026-06-15 3AMAX - Jun 15, 06:40 UTCJun 15, 07:40 UTC1h 0m
2026-06-14 3AMAX - Jun 14, 15:15 UTCJun 14, 16:05 UTC50m
2026-06-14 3AMAX - Jun 14, 14:30 UTCJun 14, 14:45 UTC15m
2026-06-14 3AMAX CEQ → CEQ Jun 14, 10:55 UTCJun 14, 11:45 UTC50m
2026-06-13 3AMAX - Jun 13, 16:05 UTCJun 13, 16:20 UTC15m
2026-06-13 3AMAX - Jun 13, 15:50 UTCJun 13, 16:00 UTC10m
2026-06-13 3AMAX - Jun 13, 15:35 UTCJun 13, 15:45 UTC10m
2026-06-13 3AMAX - Jun 13, 15:15 UTCJun 13, 15:25 UTC10m
2026-06-13 3AMAX - Jun 13, 15:00 UTCJun 13, 15:10 UTC10m
2026-06-13 3AMAX - Jun 13, 12:50 UTCJun 13, 13:40 UTC50m
2026-06-13 3AMAX MCM → NCE Jun 13, 12:20 UTCJun 13, 12:45 UTC25m
2026-06-13 3AMAX - Jun 13, 12:05 UTCJun 13, 12:15 UTC10m
2026-06-13 3AMAX - Jun 13, 11:50 UTCJun 13, 12:00 UTC10m
2026-06-13 3AMAX - Jun 13, 11:15 UTCJun 13, 11:45 UTC30m
2026-06-13 3AMAX - Jun 13, 10:25 UTCJun 13, 10:45 UTC20m
2026-06-13 3AMAX - Jun 13, 10:00 UTCJun 13, 10:20 UTC20m
2026-06-12 3AMAX - Jun 12, 11:45 UTCJun 12, 14:05 UTC2h 20m
2026-06-12 3AMAX - Jun 12, 08:30 UTCJun 12, 09:05 UTC35m
2026-06-11 3AMAX - Jun 11, 17:40 UTCJun 11, 18:05 UTC25m
2026-06-11 3AMAX - Jun 11, 17:25 UTCJun 11, 17:35 UTC10m
2026-06-11 3AMAX MCM → MCM Jun 11, 14:35 UTCJun 11, 15:05 UTC30m
2026-06-11 3AMAX - Jun 11, 12:25 UTCJun 11, 12:45 UTC20m
2026-06-11 3AMAX - Jun 11, 10:35 UTCJun 11, 11:15 UTC40m
2026-06-11 3AMAX - Jun 11, 08:25 UTCJun 11, 08:30 UTC5m
2026-06-11 3AMAX - Jun 11, 07:25 UTCJun 11, 07:40 UTC15m
2026-06-11 3AMAX - Jun 11, 07:05 UTCJun 11, 07:15 UTC10m
2026-06-10 3AMAX - Jun 10, 13:45 UTCJun 10, 13:55 UTC10m
2026-06-10 3AMAX - Jun 10, 10:55 UTCJun 10, 11:05 UTC10m
2026-06-10 3AMAX - Jun 10, 10:40 UTCJun 10, 10:50 UTC10m
2026-06-10 3AMAX - Jun 10, 10:10 UTCJun 10, 10:30 UTC20m
2026-06-10 3AMAX CEQ → MCM Jun 10, 09:35 UTCJun 10, 09:50 UTC15m
2026-06-08 3AMAX - Jun 8, 16:00 UTCJun 8, 16:15 UTC15m
2026-06-08 3AMAX - Jun 8, 14:00 UTCJun 8, 14:10 UTC10m
2026-06-08 3AMAX MCM → NCE Jun 8, 13:05 UTCJun 8, 13:15 UTC10m
2026-06-08 3AMAX NCE → MCM Jun 8, 12:50 UTCJun 8, 13:00 UTC10m
2026-06-08 3AMAX MCM → NCE Jun 8, 10:20 UTCJun 8, 12:30 UTC2h 10m
2026-06-08 3AMAX NCE → MCM Jun 8, 08:05 UTCJun 8, 10:00 UTC1h 55m
2026-06-08 3AMAX - Jun 8, 06:55 UTCJun 8, 07:00 UTC5m
2026-06-08 3AMAX MCM → MCM Jun 8, 06:30 UTCJun 8, 06:50 UTC20m
2026-06-08 3AMAX - Jun 8, 06:10 UTCJun 8, 06:25 UTC15m
2026-06-07 3AMAX - Jun 7, 18:35 UTCJun 7, 19:10 UTC35m
2026-06-07 3AMAX - Jun 7, 18:00 UTCJun 7, 18:30 UTC30m
2026-06-07 3AMAX - Jun 7, 16:50 UTCJun 7, 17:55 UTC1h 5m
2026-06-07 3AMAX - Jun 7, 15:45 UTCJun 7, 16:15 UTC30m
2026-06-07 3AMAX MCM → MCM Jun 7, 15:00 UTCJun 7, 15:40 UTC40m
2026-06-07 3AMAX - Jun 7, 12:20 UTCJun 7, 12:40 UTC20m
2026-06-07 3AMAX - Jun 7, 11:20 UTCJun 7, 11:35 UTC15m

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 3A-MAX page for operator, model, and routing details .

Mode-S 4D4020 frequently asked

What is Mode-S code 4D4020?
4D4020 is an ICAO 24-bit transponder address. Allocated to Monaco. Assigned to 3A-MAX.
Where is Mode-S 4D4020 registered?
Mode-S code 4D4020 is allocated to Monaco (MC). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D4020 broadcasting right now?
No active broadcast right now. Last signal was 15h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D4020, octal 23240040, decimal 5,062,688.
What flights does 4D4020 operate?
Mode-S 4D4020 has broadcast 1 distinct callsign, including 3AMAX.