sensors Mode-S transponder

408071

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-MDSE · PILATUS PC-12

Hex
408071
Octal
20100161
Decimal
4,227,185
Country
GB
Tail
G-MDSE
Type
PC12
Transponder active on ground
Flights observed
2
Distinct callsigns
1
Country
GB
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S 408071.

Country allocation

The ICAO 24-bit address 408071 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
EMC8 - 2 2026-04-14

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-14 EMC8 - Apr 14, 07:35 UTCApr 14, 08:05 UTC30m
2026-04-13 EMC8 - Apr 13, 14:10 UTCApr 13, 15:50 UTC1h 40m

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

Mode-S 408071 frequently asked

What is Mode-S code 408071?
408071 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-MDSE.
Where is Mode-S 408071 registered?
Mode-S code 408071 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 408071 broadcasting right now?
Mode-S 408071 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 408071, octal 20100161, decimal 4,227,185.
What flights does 408071 operate?
Mode-S 408071 has broadcast 1 distinct callsign, including EMC8.