sensors Mode-S transponder

424C81

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to M-ZPGJ · CESSNA 525C Citation CJ4

Hex
424C81
Octal
20446201
Decimal
4,344,961
Country
GB
Tail
M-ZPGJ
Type
C25C
No current signal · last broadcast 8d ago
Flights observed
26
Distinct callsigns
1
Country
GB
Last broadcast
8d ago

Last known position

Most recent position reported by Mode-S 424C81.

Country allocation

The ICAO 24-bit address 424C81 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
MZPGJ - 26 2026-06-26

Recent flights last 26

DateFlightRouteTakeoffLandingDuration
2026-06-26 MZPGJ - Jun 26, 11:14 UTCJun 26, 12:10 UTC55m
2026-06-25 MZPGJ - Jun 25, 13:45 UTCJun 25, 14:44 UTC1h 0m
2026-06-23 MZPGJ - Jun 23, 14:59 UTCJun 23, 15:59 UTC1h 0m
2026-06-23 MZPGJ ORK → GLA Jun 23, 07:19 UTCJun 23, 08:15 UTC55m
2026-06-19 MZPGJ GLA → ORK Jun 19, 09:04 UTCJun 19, 10:04 UTC1h 0m
2026-06-18 MZPGJ BQH → GLA Jun 18, 17:55 UTCJun 18, 19:00 UTC1h 5m
2026-06-18 MZPGJ GLA → BQH Jun 18, 05:35 UTCJun 18, 06:45 UTC1h 10m
2026-06-17 MZPGJ ORK → GLA Jun 17, 14:55 UTCJun 17, 15:40 UTC45m
2026-05-31 MZPGJ - May 31, 18:10 UTCMay 31, 19:00 UTC50m
2026-05-31 MZPGJ FAO → GLA May 31, 14:00 UTCMay 31, 17:05 UTC3h 5m
2026-05-28 MZPGJ ORK → FAO May 28, 14:15 UTCMay 28, 16:35 UTC2h 20m
2026-05-25 MZPGJ - May 25, 18:40 UTCMay 25, 19:30 UTC49m
2026-05-25 MZPGJ ORK → GLA May 25, 17:20 UTCMay 25, 18:10 UTC50m
2026-05-25 MZPGJ EDI → ORK May 25, 13:15 UTCMay 25, 14:10 UTC55m
2026-05-25 MZPGJ - May 25, 10:40 UTCMay 25, 12:10 UTC1h 30m
2026-05-25 MZPGJ ORK → LBG May 25, 08:20 UTCMay 25, 09:40 UTC1h 20m
2026-05-22 MZPGJ GLA → ORK May 22, 18:35 UTCMay 22, 19:35 UTC1h 0m
2026-05-22 MZPGJ ORK → GLA May 22, 14:30 UTCMay 22, 15:20 UTC50m
2026-05-22 MZPGJ - May 22, 12:00 UTCMay 22, 13:00 UTC1h 0m
2026-05-22 MZPGJ ORK → GLA May 22, 07:55 UTCMay 22, 08:45 UTC50m
2026-05-21 MZPGJ FAO → ORK May 21, 16:05 UTCMay 21, 18:20 UTC2h 15m
2026-05-19 MZPGJ - May 19, 09:20 UTCMay 19, 11:40 UTC2h 20m
2026-05-11 MZPGJ GLA → ORK May 11, 09:40 UTCMay 11, 10:30 UTC50m
2026-05-10 MZPGJ ORK → GLA May 10, 07:34 UTCMay 10, 08:35 UTC1h 0m
2026-05-03 MZPGJ LPL → ORK May 3, 17:29 UTCMay 3, 18:14 UTC45m
2026-05-03 MZPGJ ORK → LPL May 3, 09:30 UTCMay 3, 10:10 UTC40m

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

Mode-S 424C81 frequently asked

What is Mode-S code 424C81?
424C81 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to M-ZPGJ.
Where is Mode-S 424C81 registered?
Mode-S code 424C81 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 424C81 broadcasting right now?
No active broadcast right now. Last signal was 8d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 424C81, octal 20446201, decimal 4,344,961.
What flights does 424C81 operate?
Mode-S 424C81 has broadcast 1 distinct callsign, including MZPGJ.