sensors Mode-S transponder

39C5A1

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HRNB · AIRBUS A-330-900

Hex
39C5A1
Octal
16342641
Decimal
3,786,145
Country
FR
Tail
F-HRNB
Type
A339
No current signal · last broadcast 21h ago
Flights observed
2
Distinct callsigns
2
Country
FR
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S 39C5A1.

Country allocation

The ICAO 24-bit address 39C5A1 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
CRL911 Corsairfly 1 2026-04-14
CRL910 - 1 2026-04-12

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-14 CRL911 RUN → ORY Apr 14, 05:15 UTCApr 14, 05:20 UTC5m
2026-04-12 CRL910 - Apr 12, 19:25 UTCApr 12, 20:15 UTC50m

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

Mode-S 39C5A1 frequently asked

What is Mode-S code 39C5A1?
39C5A1 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HRNB.
Where is Mode-S 39C5A1 registered?
Mode-S code 39C5A1 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39C5A1 broadcasting right now?
No active broadcast right now. Last signal was 21h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39C5A1, octal 16342641, decimal 3,786,145.
What flights does 39C5A1 operate?
Mode-S 39C5A1 has broadcast 2 distinct callsigns, including CRL911, CRL910.