sensors Mode-S transponder

40688B

ICAO 24-bit transponder address · allocated to United Kingdom

Currently assigned to G-XLEA · AIRBUS A-380-800

Hex
40688B
Octal
20064213
Decimal
4,221,067
Country
GB
Tail
G-XLEA
Type
A388
Photo of G-XLEA
No current signal · last broadcast 16h ago
Flights observed
6
Distinct callsigns
3
Country
GB
Last broadcast
16h ago

Last known position

Most recent position reported by Mode-S 40688B.

Country allocation

The ICAO 24-bit address 40688B 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 3 distinct

Callsign Airline Flights Last seen
BAW213 British Airways 3 2026-04-13
BAW54 - 2 2026-04-13
BAW212 British Airways 1 2026-04-14

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 BAW212 BOS → LHR Apr 14, 05:15 UTCApr 14, 06:15 UTC1h 0m
2026-04-13 BAW213 LHR → BOS Apr 13, 19:50 UTCApr 13, 20:35 UTC45m
2026-04-13 BAW213 LHR → BOS Apr 13, 19:10 UTCApr 13, 20:10 UTC1h 0m
2026-04-13 BAW213 LHR → BOS Apr 13, 13:55 UTCApr 13, 15:10 UTC1h 15m
2026-04-13 BAW54 - Apr 13, 04:20 UTCApr 13, 06:25 UTC2h 5m
2026-04-12 BAW54 - Apr 12, 19:35 UTCApr 12, 20:05 UTC30m

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

Mode-S 40688B frequently asked

What is Mode-S code 40688B?
40688B is an ICAO 24-bit transponder address. Allocated to United Kingdom. Assigned to G-XLEA.
Where is Mode-S 40688B registered?
Mode-S code 40688B 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 40688B 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 40688B, octal 20064213, decimal 4,221,067.
What flights does 40688B operate?
Mode-S 40688B has broadcast 3 distinct callsigns, including BAW213, BAW54, BAW212.