sensors Mode-S transponder

407BB7

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-CMAH · CESSNA 152

Hex
407BB7
Octal
20075667
Decimal
4,225,975
Country
GB
Tail
G-CMAH
Type
C152
No current signal · last broadcast 1h ago
Flights observed
8
Distinct callsigns
1
Country
GB
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 407BB7.

Country allocation

The ICAO 24-bit address 407BB7 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
GCMAH - 8 2026-04-18

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-04-18 GCMAH - Apr 18, 16:35 UTCApr 18, 17:20 UTC45m
2026-04-18 GCMAH - Apr 18, 12:50 UTCApr 18, 13:50 UTC1h 0m
2026-04-18 GCMAH - Apr 18, 10:50 UTCApr 18, 12:05 UTC1h 15m
2026-04-18 GCMAH - Apr 18, 08:50 UTCApr 18, 10:00 UTC1h 10m
2026-04-16 GCMAH - Apr 16, 09:10 UTCApr 16, 10:05 UTC55m
2026-04-14 GCMAH - Apr 14, 11:05 UTCApr 14, 12:30 UTC1h 25m
2026-04-14 GCMAH - Apr 14, 09:25 UTCApr 14, 11:05 UTC1h 40m
2026-04-13 GCMAH - Apr 13, 10:05 UTCApr 13, 11:30 UTC1h 25m

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

Mode-S 407BB7 frequently asked

What is Mode-S code 407BB7?
407BB7 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-CMAH.
Where is Mode-S 407BB7 registered?
Mode-S code 407BB7 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 407BB7 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 407BB7, octal 20075667, decimal 4,225,975.
What flights does 407BB7 operate?
Mode-S 407BB7 has broadcast 1 distinct callsign, including GCMAH.