sensors Mode-S transponder

4065B3

ICAO 24-bit transponder address · allocated to United Kingdom

Hex
4065B3
Octal
20062663
Decimal
4,220,339
Country
GB
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
2
Country
GB
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4065B3.

Country allocation

The ICAO 24-bit address 4065B3 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
VIR8Y Virgin Atlantic Airways 2 2026-05-25
VIR4C Virgin Atlantic Airways 1 2026-05-22

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-25 VIR8Y LAX → LHR May 25, 08:25 UTCMay 25, 08:35 UTC10m
2026-05-22 VIR4C JFK → LHR May 22, 04:45 UTCMay 22, 05:00 UTC15m
2026-05-18 - - May 18, 04:30 UTCMay 18, 04:51 UTC21m
2026-05-05 - - May 5, 08:25 UTCMay 5, 08:40 UTC15m
2026-04-29 VIR8Y LAX → LHR Apr 29, 08:15 UTCApr 29, 08:30 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.

Mode-S 4065B3 frequently asked

What is Mode-S code 4065B3?
4065B3 is an ICAO 24-bit transponder address. Allocated to United Kingdom.
Where is Mode-S 4065B3 registered?
Mode-S code 4065B3 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 4065B3 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4065B3, octal 20062663, decimal 4,220,339.
What flights does 4065B3 operate?
Mode-S 4065B3 has broadcast 2 distinct callsigns, including VIR8Y, VIR4C.