sensors Mode-S transponder

408253

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-RGAM · DIAMOND DA-40 Club Star

Hex
408253
Octal
20101123
Decimal
4,227,667
Country
GB
Tail
G-RGAM
Type
DA40
No current signal · last broadcast 16h ago
Flights observed
5
Distinct callsigns
2
Country
GB
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S 408253.

Country allocation

The ICAO 24-bit address 408253 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 2 distinct

Callsign Airline Flights Last seen
LDG12 - 3 2026-04-13
LDG57 - 2 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 LDG57 - Apr 14, 10:25 UTCApr 14, 11:05 UTC40m
2026-04-14 LDG57 - Apr 14, 07:35 UTCApr 14, 08:55 UTC1h 20m
2026-04-13 LDG12 - Apr 13, 15:50 UTCApr 13, 16:20 UTC30m
2026-04-13 LDG12 - Apr 13, 15:05 UTCApr 13, 16:15 UTC1h 10m
2026-04-13 LDG12 OXF → OXF Apr 13, 12:35 UTCApr 13, 13:30 UTC55m

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

Mode-S 408253 frequently asked

What is Mode-S code 408253?
408253 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-RGAM.
Where is Mode-S 408253 registered?
Mode-S code 408253 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 408253 broadcasting right now?
No active broadcast right now. Last signal was 16h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 408253, octal 20101123, decimal 4,227,667.
What flights does 408253 operate?
Mode-S 408253 has broadcast 2 distinct callsigns, including LDG12, LDG57.