sensors Mode-S transponder

3981A6

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HANG · ROBINSON R-44 Raven

Hex
3981A6
Octal
16300646
Decimal
3,768,742
Country
FR
Tail
F-HANG
Type
R44
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 3981A6.

Country allocation

The ICAO 24-bit address 3981A6 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
FHANG - 5 2026-06-07

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-07 FHANG - Jun 7, 15:20 UTCJun 7, 16:05 UTC45m
2026-06-07 FHANG - Jun 7, 09:00 UTCJun 7, 09:45 UTC45m
2026-05-31 FHANG - May 31, 17:20 UTCMay 31, 18:35 UTC1h 15m
2026-05-29 FHANG - May 29, 09:05 UTCMay 29, 10:35 UTC1h 30m
2026-05-28 FHANG - May 28, 13:50 UTCMay 28, 15:05 UTC1h 15m

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

Mode-S 3981A6 frequently asked

What is Mode-S code 3981A6?
3981A6 is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HANG.
Where is Mode-S 3981A6 registered?
Mode-S code 3981A6 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3981A6 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 3981A6, octal 16300646, decimal 3,768,742.
What flights does 3981A6 operate?
Mode-S 3981A6 has broadcast 1 distinct callsign, including FHANG.