sensors Mode-S transponder

4D2489

ICAO 24-bit transponder address

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

Hex
4D2489
Octal
23222211
Decimal
5,055,625
Tail
9H-VCX
Type
CL35
Broadcasting now · callsign VJT443 · 15,000 ft
Flights observed
5
Distinct callsigns
1
Country
-
Last broadcast
1h ago

Current position

4D2489 is currently broadcasting. Map zoomed to live position.

Callsign history 1 distinct

Callsign Airline Flights Last seen
VJT443 - 5 2026-06-11

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-11 VJT443 IBZ → SZG Jun 11, 09:05 UTCJun 11, 11:05 UTC2h 0m
2026-06-10 VJT443 OPO → IBZ Jun 10, 12:50 UTCJun 10, 14:05 UTC1h 15m
2026-06-09 VJT443 LIS → OPO Jun 9, 20:55 UTCJun 9, 21:10 UTC15m
2026-06-09 VJT443 - Jun 9, 16:45 UTCJun 9, 19:45 UTC3h 0m
2026-06-09 VJT443 BMA → FAB Jun 9, 05:25 UTCJun 9, 07:40 UTC2h 15m

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

Mode-S 4D2489 frequently asked

What is Mode-S code 4D2489?
4D2489 is an ICAO 24-bit transponder address. Assigned to 9H-VCX.
Is 4D2489 broadcasting right now?
Yes. Mode-S 4D2489 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4D2489, octal 23222211, decimal 5,055,625.
What flights does 4D2489 operate?
Mode-S 4D2489 has broadcast 1 distinct callsign, including VJT443.