sensors Mode-S transponder

401552

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-ARKS · PIPER PA-22

Hex
401552
Octal
20012522
Decimal
4,199,762
Country
GB
Tail
G-ARKS
Type
PA22
No current signal · last broadcast 2d ago
Flights observed
33
Distinct callsigns
1
Country
GB
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S 401552.

Country allocation

The ICAO 24-bit address 401552 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
GARKS - 33 2026-07-11

Recent flights last 33

DateFlightRouteTakeoffLandingDuration
2026-07-11 GARKS - Jul 11, 14:30 UTCJul 11, 14:45 UTC15m
2026-07-11 GARKS - Jul 11, 11:40 UTCJul 11, 12:45 UTC1h 5m
2026-07-04 GARKS - Jul 4, 13:10 UTCJul 4, 13:25 UTC15m
2026-07-04 GARKS - Jul 4, 12:00 UTCJul 4, 12:20 UTC20m
2026-06-29 GARKS - Jun 29, 13:30 UTCJun 29, 13:54 UTC25m
2026-06-29 GARKS - Jun 29, 12:09 UTCJun 29, 12:29 UTC20m
2026-06-28 GARKS GBA → GLO Jun 28, 13:40 UTCJun 28, 14:09 UTC30m
2026-06-28 GARKS - Jun 28, 11:55 UTCJun 28, 12:19 UTC25m
2026-06-23 GARKS - Jun 23, 07:15 UTCJun 23, 07:49 UTC35m
2026-06-16 GARKS - Jun 16, 11:15 UTCJun 16, 11:30 UTC15m
2026-06-16 GARKS - Jun 16, 09:15 UTCJun 16, 09:30 UTC15m
2026-06-14 GARKS - Jun 14, 09:25 UTCJun 14, 09:35 UTC10m
2026-06-14 GARKS - Jun 14, 07:25 UTCJun 14, 07:40 UTC15m
2026-06-02 GARKS HYC → GLO Jun 2, 13:30 UTCJun 2, 14:15 UTC45m
2026-06-02 GARKS GLO → HYC Jun 2, 09:15 UTCJun 2, 09:55 UTC40m
2026-05-28 GARKS GLO → GLO May 28, 14:20 UTCMay 28, 15:20 UTC1h 0m
2026-05-21 GARKS - May 21, 15:15 UTCMay 21, 16:10 UTC55m
2026-05-18 GARKS - May 18, 11:10 UTCMay 18, 11:35 UTC25m
2026-05-18 GARKS - May 18, 08:25 UTCMay 18, 08:55 UTC30m
2026-05-15 GARKS - May 15, 08:50 UTCMay 15, 09:15 UTC25m
2026-05-14 GARKS - May 14, 08:05 UTCMay 14, 08:55 UTC50m
2026-05-12 GARKS - May 12, 12:40 UTCMay 12, 13:40 UTC1h 0m
2026-05-12 GARKS - May 12, 08:55 UTCMay 12, 10:15 UTC1h 20m
2026-05-08 GARKS - May 8, 14:35 UTCMay 8, 15:20 UTC45m
2026-05-08 GARKS - May 8, 07:44 UTCMay 8, 08:34 UTC50m
2026-05-01 GARKS GLO → GLO May 1, 11:15 UTCMay 1, 12:10 UTC55m
2026-04-30 GARKS GBA → GLO Apr 30, 15:00 UTCApr 30, 15:20 UTC20m
2026-04-30 GARKS GLO → GBA Apr 30, 13:15 UTCApr 30, 13:50 UTC35m
2026-04-30 GARKS - Apr 30, 08:25 UTCApr 30, 09:00 UTC35m
2026-04-28 GARKS - Apr 28, 15:00 UTCApr 28, 15:15 UTC15m
2026-04-28 GARKS - Apr 28, 13:40 UTCApr 28, 14:00 UTC20m
2026-04-13 GARKS - Apr 13, 15:00 UTCApr 13, 15:30 UTC30m
2026-04-13 GARKS - Apr 13, 14:00 UTCApr 13, 14:25 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-ARKS page for operator, model, and routing details .

Mode-S 401552 frequently asked

What is Mode-S code 401552?
401552 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-ARKS.
Where is Mode-S 401552 registered?
Mode-S code 401552 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 401552 broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 401552, octal 20012522, decimal 4,199,762.
What flights does 401552 operate?
Mode-S 401552 has broadcast 1 distinct callsign, including GARKS.