sensors Mode-S transponder

406A3A

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-CICO · Ultramagic H-42 Hot Air Balloon

Hex
406A3A
Octal
20065072
Decimal
4,221,498
Country
GB
Tail
G-CICO
Type
BALL
No current signal · last broadcast 4d ago
Flights observed
11
Distinct callsigns
8
Country
GB
Last broadcast
4d ago

Last known position

Most recent position reported by Mode-S 406A3A.

Country allocation

The ICAO 24-bit address 406A3A 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 8 distinct

Callsign Airline Flights Last seen
SHT9A - 1 2026-05-17
SHT6C - 1 2026-05-20
SHT3T - 1 2026-06-05
SHT19Z - 1 2026-04-29
SHT19M - 1 2026-05-19
SHT13E - 1 2026-06-19
SHT13C - 1 2026-05-31
SHT12K - 1 2026-06-19

Recent flights last 11

DateFlightRouteTakeoffLandingDuration
2026-06-19 SHT13E - Jun 19, 11:04 UTCJun 19, 11:20 UTC15m
2026-06-19 SHT12K - Jun 19, 08:20 UTCJun 19, 08:29 UTC10m
2026-06-16 - - Jun 16, 19:25 UTCJun 16, 19:35 UTC10m
2026-06-12 - - Jun 12, 15:30 UTCJun 12, 15:40 UTC10m
2026-06-05 SHT3T - Jun 5, 07:45 UTCJun 5, 08:00 UTC15m
2026-05-31 SHT13C - May 31, 09:20 UTCMay 31, 09:30 UTC10m
2026-05-21 - - May 21, 10:10 UTCMay 22, 07:00 UTC20h 50m
2026-05-20 SHT6C - May 20, 17:40 UTCMay 21, 10:15 UTC16h 35m
2026-05-19 SHT19M - May 19, 13:25 UTCMay 19, 13:35 UTC10m
2026-05-17 SHT9A - May 17, 10:20 UTCMay 17, 10:35 UTC15m
2026-04-29 SHT19Z - Apr 29, 09:05 UTCApr 29, 09:20 UTC15m

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

Mode-S 406A3A frequently asked

What is Mode-S code 406A3A?
406A3A is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-CICO.
Where is Mode-S 406A3A registered?
Mode-S code 406A3A 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 406A3A broadcasting right now?
No active broadcast right now. Last signal was 4d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 406A3A, octal 20065072, decimal 4,221,498.
What flights does 406A3A operate?
Mode-S 406A3A has broadcast 8 distinct callsigns, including SHT9A, SHT6C, SHT3T, SHT19Z, SHT19M.