sensors Mode-S transponder

3978FC

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-JFLU · AVEKO Flamingo

Hex
3978FC
Octal
16274374
Decimal
3,766,524
Country
FR
Tail
F-JFLU
Type
VL3
No current signal · last broadcast 2h ago
Flights observed
6
Distinct callsigns
1
Country
FR
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 3978FC.

Country allocation

The ICAO 24-bit address 3978FC 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
FJFLU - 6 2026-04-26

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-26 FJFLU - Apr 26, 15:10 UTCApr 26, 15:20 UTC10m
2026-04-26 FJFLU - Apr 26, 13:40 UTCApr 26, 14:30 UTC50m
2026-04-25 FJFLU - Apr 25, 08:55 UTCApr 25, 09:40 UTC45m
2026-04-25 FJFLU - Apr 25, 07:05 UTCApr 25, 07:20 UTC15m
2026-04-19 FJFLU - Apr 19, 14:40 UTCApr 19, 15:35 UTC55m
2026-04-19 FJFLU - Apr 19, 09:00 UTCApr 19, 10:40 UTC1h 40m

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

Mode-S 3978FC frequently asked

What is Mode-S code 3978FC?
3978FC is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-JFLU.
Where is Mode-S 3978FC registered?
Mode-S code 3978FC is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3978FC 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 3978FC, octal 16274374, decimal 3,766,524.
What flights does 3978FC operate?
Mode-S 3978FC has broadcast 1 distinct callsign, including FJFLU.