sensors Mode-S transponder

39723C

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-JDWJ · AEROSPOOL WT-9 Dynamic

Hex
39723C
Octal
16271074
Decimal
3,764,796
Country
FR
Tail
F-JDWJ
Type
WT9
No current signal · last broadcast 2h ago
Flights observed
5
Distinct callsigns
1
Country
FR
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 39723C.

Country allocation

The ICAO 24-bit address 39723C 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
FJDWJ - 5 2026-05-25

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-05-25 FJDWJ - May 25, 07:55 UTCMay 25, 08:40 UTC45m
2026-05-23 FJDWJ - May 23, 13:30 UTCMay 23, 14:00 UTC30m
2026-05-16 FJDWJ - May 16, 06:50 UTCMay 16, 07:05 UTC15m
2026-05-10 FJDWJ - May 10, 07:30 UTCMay 10, 07:50 UTC20m
2026-05-08 FJDWJ - May 8, 14:05 UTCMay 8, 14:20 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 F-JDWJ page for operator, model, and routing details .

Mode-S 39723C frequently asked

What is Mode-S code 39723C?
39723C is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-JDWJ.
Where is Mode-S 39723C registered?
Mode-S code 39723C is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39723C broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39723C, octal 16271074, decimal 3,764,796.
What flights does 39723C operate?
Mode-S 39723C has broadcast 1 distinct callsign, including FJDWJ.