sensors Mode-S transponder

39B239

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HMRZ · AIRPLANE FACTORY Sling 2

Hex
39B239
Octal
16331071
Decimal
3,781,177
Country
FR
Tail
F-HMRZ
Type
SLG2
Broadcasting now · callsign FHMRZ · 2,825 ft
Flights observed
6
Distinct callsigns
1
Country
FR
Last broadcast
2h ago

Current position

39B239 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 39B239 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 1 distinct

Callsign Airline Flights Last seen
FHMRZ - 6 2026-04-27

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-27 FHMRZ - Apr 27, 17:25 UTCApr 27, 18:00 UTC35m
2026-04-27 FHMRZ - Apr 27, 14:45 UTCApr 27, 15:20 UTC35m
2026-04-24 FHMRZ - Apr 24, 13:00 UTCApr 24, 13:40 UTC40m
2026-04-24 FHMRZ - Apr 24, 11:10 UTCApr 24, 11:35 UTC25m
2026-04-23 FHMRZ - Apr 23, 12:55 UTCApr 23, 14:35 UTC1h 40m
2026-04-23 FHMRZ - Apr 23, 10:55 UTCApr 23, 12:01 UTC1h 5m

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

Mode-S 39B239 frequently asked

What is Mode-S code 39B239?
39B239 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HMRZ.
Where is Mode-S 39B239 registered?
Mode-S code 39B239 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39B239 broadcasting right now?
Yes. Mode-S 39B239 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39B239, octal 16331071, decimal 3,781,177.
What flights does 39B239 operate?
Mode-S 39B239 has broadcast 1 distinct callsign, including FHMRZ.