sensors Mode-S transponder

408127

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-MACZ · BOEING 767-200

Hex
408127
Octal
20100447
Decimal
4,227,367
Country
GB
Tail
G-MACZ
Type
B762
Transponder active on ground
Flights observed
5
Distinct callsigns
3
Country
GB
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 408127.

Country allocation

The ICAO 24-bit address 408127 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 3 distinct

Callsign Airline Flights Last seen
MUK6566 - 2 2026-04-13
MUK6565 - 2 2026-04-13
SRR6565 - 1 2026-04-13

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-13 SRR6565 EMA → CGN Apr 13, 21:35 UTCApr 13, 22:40 UTC1h 5m
2026-04-13 MUK6565 - Apr 13, 19:50 UTCApr 13, 20:20 UTC30m
2026-04-13 MUK6565 - Apr 13, 19:35 UTCApr 13, 19:45 UTC10m
2026-04-13 MUK6566 - Apr 13, 04:20 UTCApr 13, 04:35 UTC15m
2026-04-13 MUK6566 - Apr 13, 03:55 UTCApr 13, 04:15 UTC20m

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 G-MACZ page for operator, model, and routing details .

Mode-S 408127 frequently asked

What is Mode-S code 408127?
408127 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-MACZ.
Where is Mode-S 408127 registered?
Mode-S code 408127 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 408127 broadcasting right now?
Mode-S 408127 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 408127, octal 20100447, decimal 4,227,367.
What flights does 408127 operate?
Mode-S 408127 has broadcast 3 distinct callsigns, including MUK6566, MUK6565, SRR6565.