sensors Mode-S transponder

40686B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-GAAL · CESSNA 560XL Citation XLS

Hex
40686B
Octal
20064153
Decimal
4,221,035
Country
GB
Tail
G-GAAL
Type
C56X
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
1
Country
GB
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 40686B.

Country allocation

The ICAO 24-bit address 40686B 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
LNX05AL - 5 2026-04-25

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-25 LNX05AL - Apr 25, 14:15 UTCApr 25, 14:40 UTC25m
2026-04-25 LNX05AL LTN → CWL Apr 25, 06:35 UTCApr 25, 07:05 UTC30m
2026-04-22 LNX05AL VLC → LTN Apr 22, 16:30 UTCApr 22, 18:45 UTC2h 15m
2026-04-22 LNX05AL MAD → VLC Apr 22, 13:25 UTCApr 22, 14:00 UTC35m
2026-04-22 LNX05AL - Apr 22, 06:30 UTCApr 22, 08:45 UTC2h 15m

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

Mode-S 40686B frequently asked

What is Mode-S code 40686B?
40686B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-GAAL.
Where is Mode-S 40686B registered?
Mode-S code 40686B 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 40686B broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 40686B, octal 20064153, decimal 4,221,035.
What flights does 40686B operate?
Mode-S 40686B has broadcast 1 distinct callsign, including LNX05AL.