sensors Mode-S transponder

404509

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-BZUY · VANS RV-6

Hex
404509
Octal
20042411
Decimal
4,211,977
Country
GB
Tail
G-BZUY
Type
RV6
No current signal · last broadcast 2d ago
Flights observed
2
Distinct callsigns
1
Country
GB
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S 404509.

Country allocation

The ICAO 24-bit address 404509 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
GBZUY - 2 2026-04-19

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-19 GBZUY - Apr 19, 13:15 UTCApr 19, 14:10 UTC55m
2026-04-19 GBZUY - Apr 19, 10:30 UTCApr 19, 11:10 UTC40m

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

Mode-S 404509 frequently asked

What is Mode-S code 404509?
404509 is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-BZUY.
Where is Mode-S 404509 registered?
Mode-S code 404509 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 404509 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 404509, octal 20042411, decimal 4,211,977.
What flights does 404509 operate?
Mode-S 404509 has broadcast 1 distinct callsign, including GBZUY.