sensors Mode-S transponder

4D2359

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-ELF · BOEING 737-700

Hex
4D2359
Octal
23221531
Decimal
5,055,321
Country
MT
Tail
9H-ELF
Type
B737
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
3
Country
MT
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 4D2359.

Country allocation

The ICAO 24-bit address 4D2359 falls within the block assigned to Malta (MT) by ICAO Annex 10, Volume III. Every aircraft registered in Malta 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 3 distinct

Callsign Airline Flights Last seen
AXY775A - 2 2026-04-16
AXY765Y - 2 2026-04-14
AXY449J - 1 2026-04-19

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-19 AXY449J - Apr 19, 12:30 UTCApr 19, 14:00 UTC1h 30m
2026-04-16 AXY775A - Apr 16, 15:15 UTCApr 16, 16:00 UTC45m
2026-04-16 AXY775A - Apr 16, 14:20 UTCApr 16, 15:10 UTC50m
2026-04-14 AXY765Y - Apr 14, 09:10 UTCApr 14, 09:25 UTC15m
2026-04-14 AXY765Y - Apr 14, 08:15 UTCApr 14, 09:05 UTC50m

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 9H-ELF page for operator, model, and routing details .

Mode-S 4D2359 frequently asked

What is Mode-S code 4D2359?
4D2359 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-ELF.
Where is Mode-S 4D2359 registered?
Mode-S code 4D2359 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D2359 broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2359, octal 23221531, decimal 5,055,321.
What flights does 4D2359 operate?
Mode-S 4D2359 has broadcast 3 distinct callsigns, including AXY775A, AXY765Y, AXY449J.