sensors Mode-S transponder

393458

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-GNCY · DIAMOND DA-40 Club Star

Hex
393458
Octal
16232130
Decimal
3,748,952
Country
FR
Tail
F-GNCY
Type
DA40
No current signal · last broadcast 4h ago
Flights observed
7
Distinct callsigns
1
Country
FR
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S 393458.

Country allocation

The ICAO 24-bit address 393458 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
FGNCY - 7 2026-04-18

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-18 FGNCY - Apr 18, 12:40 UTCApr 18, 13:25 UTC45m
2026-04-17 FGNCY - Apr 17, 17:00 UTCApr 17, 17:15 UTC15m
2026-04-17 FGNCY - Apr 17, 12:00 UTCApr 17, 12:30 UTC30m
2026-04-17 FGNCY - Apr 17, 08:05 UTCApr 17, 09:00 UTC55m
2026-04-16 FGNCY - Apr 16, 11:49 UTCApr 16, 12:45 UTC55m
2026-04-15 FGNCY - Apr 15, 13:01 UTCApr 15, 13:40 UTC40m
2026-04-15 FGNCY - Apr 15, 09:10 UTCApr 15, 09:55 UTC45m

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

Mode-S 393458 frequently asked

What is Mode-S code 393458?
393458 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-GNCY.
Where is Mode-S 393458 registered?
Mode-S code 393458 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 393458 broadcasting right now?
No active broadcast right now. Last signal was 4h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 393458, octal 16232130, decimal 3,748,952.
What flights does 393458 operate?
Mode-S 393458 has broadcast 1 distinct callsign, including FGNCY.