sensors Mode-S transponder

39854B

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HBKL · AIRBUS HELICOPTERS EC-120

Hex
39854B
Octal
16302513
Decimal
3,769,675
Country
FR
Tail
F-HBKL
Type
EC20
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
2
Country
FR
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 39854B.

Country allocation

The ICAO 24-bit address 39854B falls within the block assigned to France (FR) by ICAO Annex 10, Volume III. Every aircraft registered in France 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
FHBKL - 3 2026-04-17
FMY8782 - 1 2026-04-14

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-17 FHBKL - Apr 17, 09:20 UTCApr 17, 10:00 UTC40m
2026-04-17 FHBKL - Apr 17, 08:10 UTCApr 17, 09:10 UTC1h 0m
2026-04-16 FHBKL - Apr 16, 06:34 UTCApr 16, 06:55 UTC20m
2026-04-14 FMY8782 - Apr 14, 07:15 UTCApr 14, 08:45 UTC1h 30m

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 F-HBKL page for operator, model, and routing details .

Mode-S 39854B frequently asked

What is Mode-S code 39854B?
39854B is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HBKL.
Where is Mode-S 39854B registered?
Mode-S code 39854B is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39854B broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39854B, octal 16302513, decimal 3,769,675.
What flights does 39854B operate?
Mode-S 39854B has broadcast 2 distinct callsigns, including FHBKL, FMY8782.