sensors Mode-S transponder

406D2D

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-MCGI · SIKORSKY S-92 Helibus

Hex
406D2D
Octal
20066455
Decimal
4,222,253
Country
GB
Tail
G-MCGI
Type
S92
Broadcasting now · callsign SRG912A · 1,125 ft
Flights observed
49
Distinct callsigns
9
Country
GB
Last broadcast
1h ago

Current position

406D2D is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 406D2D 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 9 distinct

Callsign Airline Flights Last seen
SRG924A - 13 2026-05-23
SRD924 - 11 2026-05-24
SRD936 - 6 2026-04-22
SRG924 - 5 2026-05-05
SRG912A - 5 2026-06-02
SRG936A - 4 2026-05-07
SRD912 - 3 2026-06-01
SRG912E - 1 2026-05-30
SRD925 - 1 2026-05-29

Recent flights last 49

DateFlightRouteTakeoffLandingDuration
2026-06-02 SRG912A - Jun 2, 22:10 UTCJun 2, 22:25 UTC15m
2026-06-01 SRD912 HUY → HUY Jun 1, 08:50 UTCJun 1, 10:35 UTC1h 45m
2026-05-31 SRD912 - May 31, 08:25 UTCMay 31, 10:10 UTC1h 45m
2026-05-30 SRG912E - May 30, 14:20 UTCMay 30, 14:45 UTC25m
2026-05-30 SRG912A - May 30, 13:20 UTCMay 30, 13:30 UTC10m
2026-05-30 SRG912A - May 30, 12:00 UTCMay 30, 12:25 UTC25m
2026-05-30 SRG912A - May 30, 03:10 UTCMay 30, 04:25 UTC1h 15m
2026-05-29 SRG912A - May 29, 15:35 UTCMay 29, 16:40 UTC1h 5m
2026-05-29 SRD925 NQY → HUY May 29, 09:35 UTCMay 29, 11:55 UTC2h 20m
2026-05-24 SRD924 - May 24, 08:50 UTCMay 24, 09:15 UTC25m
2026-05-23 SRG924A - May 23, 19:10 UTCMay 23, 19:25 UTC15m
2026-05-23 SRG924A - May 23, 13:55 UTCMay 23, 14:10 UTC15m
2026-05-23 SRG924A - May 23, 12:55 UTCMay 23, 13:05 UTC10m
2026-05-23 SRD924 - May 23, 08:35 UTCMay 23, 10:25 UTC1h 50m
2026-05-22 SRG924A NQY → NQY May 22, 14:45 UTCMay 22, 15:10 UTC25m
2026-05-21 SRG924A - May 21, 16:40 UTCMay 21, 17:45 UTC1h 5m
2026-05-21 SRD924 NQY → NQY May 21, 14:00 UTCMay 21, 15:30 UTC1h 30m
2026-05-20 SRG924A - May 20, 20:30 UTCMay 20, 20:50 UTC20m
2026-05-20 SRG924A - May 20, 18:55 UTCMay 20, 19:40 UTC45m
2026-05-20 SRD924 - May 20, 17:30 UTCMay 20, 17:45 UTC15m
2026-05-13 SRG924A - May 13, 02:25 UTCMay 13, 02:35 UTC10m
2026-05-13 SRG924A - May 13, 01:00 UTCMay 13, 01:15 UTC15m
2026-05-12 SRG924A - May 12, 15:05 UTCMay 12, 15:20 UTC15m
2026-05-10 SRG924A - May 10, 05:25 UTCMay 10, 06:50 UTC1h 25m
2026-05-09 SRD924 - May 9, 13:50 UTCMay 9, 14:45 UTC55m
2026-05-09 SRD924 - May 9, 09:05 UTCMay 9, 09:25 UTC20m
2026-05-08 SRG924A NQY → NQY May 8, 14:05 UTCMay 8, 16:10 UTC2h 5m
2026-05-07 SRG924A - May 7, 18:40 UTCMay 7, 18:55 UTC15m
2026-05-07 SRG936A - May 7, 16:55 UTCMay 7, 17:30 UTC35m
2026-05-07 SRG936A - May 7, 16:10 UTCMay 7, 16:20 UTC10m
2026-05-06 SRD924 NQY → NQY May 6, 13:50 UTCMay 6, 15:25 UTC1h 35m
2026-05-06 SRD924 NQY → NQY May 6, 08:40 UTCMay 6, 10:20 UTC1h 40m
2026-05-05 SRG924 - May 5, 15:05 UTCMay 5, 15:15 UTC10m
2026-05-05 SRG924 - May 5, 14:05 UTCMay 5, 14:20 UTC15m
2026-05-01 SRG924 NQY → NQY May 1, 22:45 UTCMay 2, 00:00 UTC1h 15m
2026-05-01 SRG924 NQY → NQY May 1, 19:35 UTCMay 1, 21:55 UTC2h 20m
2026-05-01 SRD924 - May 1, 15:45 UTCMay 1, 16:00 UTC15m
2026-05-01 SRD924 - May 1, 14:15 UTCMay 1, 15:10 UTC55m
2026-05-01 SRG924 - May 1, 11:20 UTCMay 1, 11:35 UTC15m
2026-04-29 SRD924 NQY → NQY Apr 29, 10:05 UTCApr 29, 11:15 UTC1h 10m
2026-04-28 SRD912 - Apr 28, 13:55 UTCApr 28, 14:40 UTC45m
2026-04-23 SRG936A - Apr 23, 10:55 UTCApr 23, 11:25 UTC30m
2026-04-23 SRG936A - Apr 23, 09:35 UTCApr 23, 10:05 UTC30m
2026-04-22 SRD936 - Apr 22, 18:55 UTCApr 22, 20:05 UTC1h 10m
2026-04-17 SRD936 - Apr 17, 20:45 UTCApr 17, 21:00 UTC15m
2026-04-17 SRD936 - Apr 17, 19:30 UTCApr 17, 20:00 UTC30m
2026-04-17 SRD936 - Apr 17, 14:45 UTCApr 17, 14:55 UTC9m
2026-04-17 SRD936 - Apr 17, 13:35 UTCApr 17, 13:55 UTC20m
2026-04-12 SRD936 - Apr 12, 19:35 UTCApr 12, 19:45 UTC10m

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

Mode-S 406D2D frequently asked

What is Mode-S code 406D2D?
406D2D is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-MCGI.
Where is Mode-S 406D2D registered?
Mode-S code 406D2D 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 406D2D broadcasting right now?
Yes. Mode-S 406D2D is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 406D2D, octal 20066455, decimal 4,222,253.
What flights does 406D2D operate?
Mode-S 406D2D has broadcast 9 distinct callsigns, including SRG924A, SRD924, SRD936, SRG924, SRG912A.