sensors Mode-S transponder

4D2149

ICAO 24-bit transponder address · allocated to Malta

Currently assigned to 9H-VCO · BOMBARDIER BD-100 Challenger 350

Hex
4D2149
Octal
23220511
Decimal
5,054,793
Country
MT
Tail
9H-VCO
Type
CL35
No current signal · last broadcast 21h ago
Flights observed
4
Distinct callsigns
1
Country
MT
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S 4D2149.

Country allocation

The ICAO 24-bit address 4D2149 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 1 distinct

Callsign Airline Flights Last seen
VJT449 - 4 2026-04-14

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-14 VJT449 - Apr 14, 10:40 UTCApr 14, 11:05 UTC25m
2026-04-13 VJT449 - Apr 13, 08:20 UTCApr 13, 09:15 UTC55m
2026-04-13 VJT449 - Apr 13, 07:55 UTCApr 13, 08:15 UTC20m
2026-04-13 VJT449 VNO → BMA Apr 13, 05:20 UTCApr 13, 06:25 UTC1h 5m

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-VCO page for operator, model, and routing details .

Mode-S 4D2149 frequently asked

What is Mode-S code 4D2149?
4D2149 is an ICAO 24-bit transponder address. Allocated to Malta. Assigned to 9H-VCO.
Where is Mode-S 4D2149 registered?
Mode-S code 4D2149 is allocated to Malta (MT). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4D2149 broadcasting right now?
No active broadcast right now. Last signal was 21h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2149, octal 23220511, decimal 5,054,793.
What flights does 4D2149 operate?
Mode-S 4D2149 has broadcast 1 distinct callsign, including VJT449.