sensors Mode-S transponder

406E7B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-CIRT · ROTORSPORT MTOSport

Hex
406E7B
Octal
20067173
Decimal
4,222,587
Country
GB
Tail
G-CIRT
Type
MT
No current signal · last broadcast 5h ago
Flights observed
5
Distinct callsigns
2
Country
GB
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S 406E7B.

Country allocation

The ICAO 24-bit address 406E7B 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
GCIRT - 2 2026-05-02
TOM5XJ TUI Airways 1 2026-05-18

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-20 - - May 20, 15:40 UTCMay 20, 15:50 UTC10m
2026-05-18 TOM5XJ BHX → SSH May 18, 01:35 UTCMay 18, 01:45 UTC10m
2026-05-06 - - May 6, 22:50 UTCMay 6, 23:00 UTC10m
2026-05-02 GCIRT - May 2, 09:10 UTCMay 2, 09:55 UTC45m
2026-04-27 GCIRT - Apr 27, 15:00 UTCApr 27, 15:50 UTC50m

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

Mode-S 406E7B frequently asked

What is Mode-S code 406E7B?
406E7B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-CIRT.
Where is Mode-S 406E7B registered?
Mode-S code 406E7B 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 406E7B broadcasting right now?
No active broadcast right now. Last signal was 5h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 406E7B, octal 20067173, decimal 4,222,587.
What flights does 406E7B operate?
Mode-S 406E7B has broadcast 2 distinct callsigns, including GCIRT, TOM5XJ.