sensors Mode-S transponder

424837

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to VP-CTM · BOMBARDIER BD-700 Global 7000/7500

Hex
424837
Octal
20444067
Decimal
4,343,863
Country
GB
Tail
VP-CTM
Type
GL7T
Broadcasting now · callsign VPCTM · 44,975 ft
Flights observed
5
Distinct callsigns
1
Country
GB
Last broadcast
2h ago

Current position

424837 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 424837 falls within the block assigned to United Kingdom (GB) by ICAO Annex 10, Volume III. Every aircraft registered in United Kingdom 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
VPCTM - 5 2026-06-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-14 VPCTM - Jun 14, 22:15 UTCJun 14, 22:50 UTC35m
2026-05-31 VPCTM - May 31, 17:45 UTCMay 31, 17:55 UTC10m
2026-05-16 VPCTM - May 16, 18:00 UTCMay 16, 18:15 UTC15m
2026-05-02 VPCTM - May 2, 16:50 UTCMay 2, 17:00 UTC10m
2026-04-27 VPCTM - Apr 27, 12:25 UTCApr 27, 12:40 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 VP-CTM page for operator, model, and routing details .

Mode-S 424837 frequently asked

What is Mode-S code 424837?
424837 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to VP-CTM.
Where is Mode-S 424837 registered?
Mode-S code 424837 is allocated to United Kingdom (GB). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 424837 broadcasting right now?
Yes. Mode-S 424837 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 424837, octal 20444067, decimal 4,343,863.
What flights does 424837 operate?
Mode-S 424837 has broadcast 1 distinct callsign, including VPCTM.