sensors Mode-S transponder

424C5B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to M-JSDT · BOMBARDIER BD-700 Global 6000/6500

Hex
424C5B
Octal
20446133
Decimal
4,344,923
Country
GB
Tail
M-JSDT
Type
GLEX
No current signal · last broadcast 6d ago
Flights observed
15
Distinct callsigns
2
Country
GB
Last broadcast
6d ago

Last known position

Most recent position reported by Mode-S 424C5B.

Country allocation

The ICAO 24-bit address 424C5B 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 2 distinct

Callsign Airline Flights Last seen
MJSDT - 14 2026-06-22
BOMBARD1 - 1 2026-06-21

Recent flights last 15

DateFlightRouteTakeoffLandingDuration
2026-06-22 MJSDT - Jun 22, 18:54 UTCJun 22, 19:19 UTC25m
2026-06-22 MJSDT - Jun 22, 05:04 UTCJun 22, 15:50 UTC10h 45m
2026-06-21 BOMBARD1 BQH → STN Jun 21, 19:09 UTCJun 21, 19:24 UTC15m
2026-06-07 MJSDT - Jun 7, 16:25 UTCJun 7, 17:35 UTC1h 10m
2026-06-07 MJSDT - Jun 7, 10:40 UTCJun 7, 15:45 UTC5h 5m
2026-06-05 MJSDT BQH → ALB Jun 5, 07:45 UTCJun 5, 14:30 UTC6h 45m
2026-06-04 MJSDT CPT → BQH Jun 4, 03:10 UTCJun 4, 18:00 UTC14h 50m
2026-05-19 MJSDT - May 19, 18:25 UTCMay 19, 18:50 UTC25m
2026-05-19 MJSDT - May 19, 05:10 UTCMay 19, 15:40 UTC10h 30m
2026-05-17 MJSDT VLC → STN May 17, 14:15 UTCMay 17, 16:05 UTC1h 50m
2026-05-14 MJSDT - May 14, 18:30 UTCMay 14, 20:15 UTC1h 45m
2026-05-14 MJSDT YUL → FAB May 14, 10:50 UTCMay 14, 16:40 UTC5h 50m
2026-05-11 MJSDT - May 11, 10:20 UTCMay 11, 16:05 UTC5h 45m
2026-05-11 MJSDT - May 11, 07:50 UTCMay 11, 08:55 UTC1h 5m
2026-05-10 MJSDT - May 10, 03:20 UTCMay 10, 17:40 UTC14h 20m

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 M-JSDT page for operator, model, and routing details .

Mode-S 424C5B frequently asked

What is Mode-S code 424C5B?
424C5B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to M-JSDT.
Where is Mode-S 424C5B registered?
Mode-S code 424C5B 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 424C5B broadcasting right now?
No active broadcast right now. Last signal was 6d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 424C5B, octal 20446133, decimal 4,344,923.
What flights does 424C5B operate?
Mode-S 424C5B has broadcast 2 distinct callsigns, including MJSDT, BOMBARD1.