sensors Mode-S transponder

4D237B

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-SMG · AIRBUS A-330-300

Hex
4D237B
Octal
23221573
Decimal
5,055,355
Country
MT
Tail
9H-SMG
Type
A333
No current signal · last broadcast 13h ago
Flights observed
2
Distinct callsigns
2
Country
MT
Last broadcast
13h ago

Last known position

Most recent position reported by Mode-S 4D237B.

Country allocation

The ICAO 24-bit address 4D237B 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 2 distinct

Callsign Airline Flights Last seen
RYR21JR Ryanair 1 2026-05-14
RYR1715 Ryanair 1 2026-05-29

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-05-29 RYR1715 CFU → DUB May 29, 17:25 UTCMay 29, 17:40 UTC15m
2026-05-14 RYR21JR ALC → PIK May 14, 16:40 UTCMay 14, 16:50 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 9H-SMG page for operator, model, and routing details .

Mode-S 4D237B frequently asked

What is Mode-S code 4D237B?
4D237B is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-SMG.
Where is Mode-S 4D237B registered?
Mode-S code 4D237B is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D237B broadcasting right now?
No active broadcast right now. Last signal was 13h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D237B, octal 23221573, decimal 5,055,355.
What flights does 4D237B operate?
Mode-S 4D237B has broadcast 2 distinct callsigns, including RYR21JR, RYR1715.