sensors Mode-S transponder

40819B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-KKRV · VANS RV-7

Hex
40819B
Octal
20100633
Decimal
4,227,483
Country
GB
Tail
G-KKRV
Type
RV7
No current signal · last broadcast 27d ago
Flights observed
4
Distinct callsigns
1
Country
GB
Last broadcast
27d ago

Last known position

Most recent position reported by Mode-S 40819B.

Country allocation

The ICAO 24-bit address 40819B 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
GKKRV - 4 2026-05-14

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-05-14 GKKRV - May 14, 08:20 UTCMay 14, 08:30 UTC10m
2026-05-12 GKKRV - May 12, 07:55 UTCMay 12, 08:10 UTC15m
2026-04-22 GKKRV - Apr 22, 09:25 UTCApr 22, 10:10 UTC45m
2026-04-22 GKKRV SOU → QUG Apr 22, 08:35 UTCApr 22, 08:50 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-KKRV page for operator, model, and routing details .

Mode-S 40819B frequently asked

What is Mode-S code 40819B?
40819B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-KKRV.
Where is Mode-S 40819B registered?
Mode-S code 40819B 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 40819B broadcasting right now?
No active broadcast right now. Last signal was 27d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 40819B, octal 20100633, decimal 4,227,483.
What flights does 40819B operate?
Mode-S 40819B has broadcast 1 distinct callsign, including GKKRV.