sensors Mode-S transponder

40309D

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-BRXH · CESSNA 120

Hex
40309D
Octal
20030235
Decimal
4,206,749
Country
GB
Tail
G-BRXH
Type
C120
No current signal · last broadcast 18h ago
Flights observed
45
Distinct callsigns
1
Country
GB
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S 40309D.

Country allocation

The ICAO 24-bit address 40309D 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
GBRXH - 45 2026-07-23

Recent flights last 45

DateFlightRouteTakeoffLandingDuration
2026-07-23 GBRXH - Jul 23, 12:20 UTCJul 23, 13:25 UTC1h 5m
2026-07-23 GBRXH - Jul 23, 09:55 UTCJul 23, 10:50 UTC55m
2026-07-22 GBRXH - Jul 22, 13:10 UTCJul 22, 14:10 UTC1h 0m
2026-07-11 GBRXH - Jul 11, 17:45 UTCJul 11, 19:20 UTC1h 35m
2026-07-11 GBRXH - Jul 11, 16:00 UTCJul 11, 16:50 UTC50m
2026-07-10 GBRXH - Jul 10, 11:15 UTCJul 10, 12:05 UTC50m
2026-07-10 GBRXH - Jul 10, 08:50 UTCJul 10, 10:00 UTC1h 10m
2026-07-10 GBRXH - Jul 10, 07:45 UTCJul 10, 08:00 UTC15m
2026-07-09 GBRXH - Jul 9, 14:05 UTCJul 9, 16:15 UTC2h 10m
2026-07-09 GBRXH - Jul 9, 12:05 UTCJul 9, 12:40 UTC35m
2026-07-09 GBRXH - Jul 9, 09:05 UTCJul 9, 11:35 UTC2h 30m
2026-07-05 GBRXH - Jul 5, 14:05 UTCJul 5, 15:05 UTC1h 0m
2026-07-05 GBRXH - Jul 5, 10:20 UTCJul 5, 11:15 UTC55m
2026-07-04 GBRXH - Jul 4, 12:30 UTCJul 4, 13:20 UTC50m
2026-07-04 GBRXH - Jul 4, 09:50 UTCJul 4, 10:35 UTC45m
2026-06-26 GBRXH - Jun 26, 08:05 UTCJun 26, 09:30 UTC1h 25m
2026-06-23 GBRXH - Jun 23, 14:44 UTCJun 23, 15:40 UTC55m
2026-06-23 GBRXH - Jun 23, 13:59 UTCJun 23, 14:10 UTC10m
2026-06-21 GBRXH - Jun 21, 12:44 UTCJun 21, 13:24 UTC40m
2026-06-21 GBRXH - Jun 21, 10:54 UTCJun 21, 11:30 UTC35m
2026-06-21 GBRXH - Jun 21, 09:15 UTCJun 21, 09:29 UTC15m
2026-06-20 GBRXH RCS → RCS Jun 20, 13:09 UTCJun 20, 14:19 UTC1h 10m
2026-06-18 GBRXH - Jun 18, 14:45 UTCJun 18, 15:40 UTC55m
2026-06-18 GBRXH - Jun 18, 11:00 UTCJun 18, 12:00 UTC1h 0m
2026-06-13 GBRXH RCS → RCS Jun 13, 08:40 UTCJun 13, 09:15 UTC35m
2026-06-10 GBRXH RCS → RCS Jun 10, 08:55 UTCJun 10, 09:40 UTC45m
2026-05-31 GBRXH RCS → RCS May 31, 12:55 UTCMay 31, 14:15 UTC1h 20m
2026-05-25 GBRXH - May 25, 12:15 UTCMay 25, 12:55 UTC40m
2026-05-24 GBRXH - May 24, 14:55 UTCMay 24, 15:30 UTC35m
2026-05-24 GBRXH - May 24, 09:50 UTCMay 24, 10:15 UTC25m
2026-05-18 GBRXH - May 18, 10:45 UTCMay 18, 11:10 UTC25m
2026-05-18 GBRXH - May 18, 09:05 UTCMay 18, 09:25 UTC20m
2026-05-09 GBRXH - May 9, 13:25 UTCMay 9, 14:20 UTC55m
2026-05-09 GBRXH - May 9, 09:30 UTCMay 9, 10:30 UTC1h 0m
2026-05-02 GBRXH - May 2, 12:20 UTCMay 2, 13:15 UTC55m
2026-05-02 GBRXH RCS → RCS May 2, 10:25 UTCMay 2, 11:10 UTC45m
2026-04-30 GBRXH - Apr 30, 13:40 UTCApr 30, 15:30 UTC1h 50m
2026-04-26 GBRXH - Apr 26, 14:00 UTCApr 26, 15:30 UTC1h 30m
2026-04-26 GBRXH - Apr 26, 08:30 UTCApr 26, 09:45 UTC1h 15m
2026-04-25 GBRXH - Apr 25, 15:35 UTCApr 25, 15:55 UTC20m
2026-04-25 GBRXH - Apr 25, 13:25 UTCApr 25, 13:40 UTC15m
2026-04-24 GBRXH - Apr 24, 14:25 UTCApr 24, 16:05 UTC1h 40m
2026-04-24 GBRXH - Apr 24, 10:55 UTCApr 24, 11:45 UTC50m
2026-04-21 GBRXH - Apr 21, 10:05 UTCApr 21, 10:25 UTC20m
2026-04-20 GBRXH - Apr 20, 12:15 UTCApr 20, 12:40 UTC25m

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

Mode-S 40309D frequently asked

What is Mode-S code 40309D?
40309D is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-BRXH.
Where is Mode-S 40309D registered?
Mode-S code 40309D 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 40309D broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 40309D, octal 20030235, decimal 4,206,749.
What flights does 40309D operate?
Mode-S 40309D has broadcast 1 distinct callsign, including GBRXH.