sensors Mode-S transponder

424B7C

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to M-LDYS · AIRBUS HELICOPTERS EC-145

Hex
424B7C
Octal
20445574
Decimal
4,344,700
Country
GB
Tail
M-LDYS
Type
EC45
No current signal · last broadcast 2d ago
Flights observed
92
Distinct callsigns
5
Country
GB
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S 424B7C.

Country allocation

The ICAO 24-bit address 424B7C 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 5 distinct

Callsign Airline Flights Last seen
MLDYS - 75 2026-06-25
GOLD4 - 6 2026-06-20
GOLD04 - 5 2026-06-18
SSP24 - 4 2026-06-16
SSP17 - 2 2026-06-19

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-25 MLDYS - Jun 25, 08:40 UTCJun 25, 09:05 UTC25m
2026-06-24 MLDYS - Jun 24, 13:54 UTCJun 24, 14:24 UTC30m
2026-06-24 MLDYS - Jun 24, 11:05 UTCJun 24, 11:50 UTC45m
2026-06-23 MLDYS - Jun 23, 13:34 UTCJun 23, 14:44 UTC1h 10m
2026-06-23 MLDYS - Jun 23, 11:10 UTCJun 23, 12:20 UTC1h 10m
2026-06-23 MLDYS LYN → CEQ Jun 23, 08:15 UTCJun 23, 09:49 UTC1h 35m
2026-06-22 MLDYS - Jun 22, 14:05 UTCJun 22, 14:29 UTC25m
2026-06-22 MLDYS - Jun 22, 09:34 UTCJun 22, 11:39 UTC2h 5m
2026-06-20 GOLD4 - Jun 20, 18:14 UTCJun 20, 18:29 UTC15m
2026-06-20 GOLD4 - Jun 20, 17:19 UTCJun 20, 18:04 UTC45m
2026-06-20 GOLD4 - Jun 20, 16:49 UTCJun 20, 17:04 UTC15m
2026-06-20 GOLD4 - Jun 20, 10:44 UTCJun 20, 11:05 UTC20m
2026-06-20 GOLD4 - Jun 20, 09:44 UTCJun 20, 10:34 UTC50m
2026-06-20 GOLD4 - Jun 20, 09:14 UTCJun 20, 09:29 UTC15m
2026-06-19 SSP17 - Jun 19, 16:25 UTCJun 19, 16:34 UTC10m
2026-06-19 SSP17 - Jun 19, 15:19 UTCJun 19, 16:14 UTC55m
2026-06-18 GOLD04 - Jun 18, 18:55 UTCJun 18, 19:05 UTC10m
2026-06-18 GOLD04 - Jun 18, 18:20 UTCJun 18, 18:40 UTC20m
2026-06-18 GOLD04 - Jun 18, 17:50 UTCJun 18, 18:05 UTC15m
2026-06-18 GOLD04 - Jun 18, 13:05 UTCJun 18, 13:25 UTC20m
2026-06-18 GOLD04 - Jun 18, 12:05 UTCJun 18, 12:45 UTC40m
2026-06-18 MLDYS - Jun 18, 10:45 UTCJun 18, 11:55 UTC1h 10m
2026-06-16 SSP24 - Jun 16, 16:15 UTCJun 16, 16:30 UTC15m
2026-06-16 SSP24 - Jun 16, 15:30 UTCJun 16, 16:05 UTC35m
2026-06-16 SSP24 - Jun 16, 12:14 UTCJun 16, 12:55 UTC40m
2026-06-16 SSP24 - Jun 16, 11:49 UTCJun 16, 12:05 UTC15m
2026-06-15 MLDYS - Jun 15, 18:04 UTCJun 15, 18:50 UTC45m
2026-06-15 MLDYS - Jun 15, 17:40 UTCJun 15, 17:54 UTC15m
2026-06-10 MLDYS - Jun 10, 07:55 UTCJun 10, 09:20 UTC1h 25m
2026-06-09 MLDYS - Jun 9, 16:45 UTCJun 9, 17:15 UTC30m
2026-06-09 MLDYS - Jun 9, 15:35 UTCJun 9, 15:50 UTC15m
2026-06-09 MLDYS - Jun 9, 12:35 UTCJun 9, 14:25 UTC1h 50m
2026-06-09 MLDYS - Jun 9, 07:40 UTCJun 9, 08:10 UTC30m
2026-06-08 MLDYS - Jun 8, 17:00 UTCJun 8, 17:35 UTC35m
2026-06-08 MLDYS - Jun 8, 16:40 UTCJun 8, 16:50 UTC10m
2026-06-08 MLDYS - Jun 8, 16:15 UTCJun 8, 16:20 UTC5m
2026-06-08 MLDYS - Jun 8, 15:50 UTCJun 8, 16:00 UTC10m
2026-06-05 MLDYS - Jun 5, 15:10 UTCJun 5, 15:15 UTC5m
2026-06-03 MLDYS - Jun 3, 13:45 UTCJun 3, 13:55 UTC10m
2026-06-03 MLDYS - Jun 3, 10:00 UTCJun 3, 10:05 UTC5m
2026-06-02 MLDYS - Jun 2, 13:20 UTCJun 2, 13:45 UTC25m
2026-06-02 MLDYS - Jun 2, 12:50 UTCJun 2, 13:05 UTC15m
2026-06-02 MLDYS - Jun 2, 11:55 UTCJun 2, 12:35 UTC40m
2026-06-02 MLDYS - Jun 2, 08:40 UTCJun 2, 09:20 UTC40m
2026-05-31 MLDYS - May 31, 18:05 UTCMay 31, 18:15 UTC10m
2026-05-31 MLDYS - May 31, 17:05 UTCMay 31, 17:10 UTC5m
2026-05-31 MLDYS - May 31, 15:35 UTCMay 31, 16:00 UTC25m
2026-05-31 MLDYS - May 31, 09:40 UTCMay 31, 10:00 UTC20m
2026-05-30 MLDYS - May 30, 17:10 UTCMay 30, 17:25 UTC15m
2026-05-30 MLDYS - May 30, 10:35 UTCMay 30, 10:45 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 M-LDYS page for operator, model, and routing details .

Mode-S 424B7C frequently asked

What is Mode-S code 424B7C?
424B7C is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to M-LDYS.
Where is Mode-S 424B7C registered?
Mode-S code 424B7C 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 424B7C broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 424B7C, octal 20445574, decimal 4,344,700.
What flights does 424B7C operate?
Mode-S 424B7C has broadcast 5 distinct callsigns, including MLDYS, GOLD4, GOLD04, SSP24, SSP17.