sensors Mode-S transponder

39990E

ICAO 24-bit transponder address · allocated to France

Currently assigned to F-HGIO · CESSNA 510 Citation Mustang

Hex
39990E
Octal
16314416
Decimal
3,774,734
Country
FR
Tail
F-HGIO
Type
C510
No current signal · last broadcast 4h ago
Flights observed
5
Distinct callsigns
1
Country
FR
Last broadcast
4h ago

Last known position

Most recent position reported by Mode-S 39990E.

Country allocation

The ICAO 24-bit address 39990E 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
ASJ02IO - 5 2026-04-28

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-28 ASJ02IO - Apr 28, 15:30 UTCApr 28, 16:30 UTC1h 0m
2026-04-28 ASJ02IO - Apr 28, 08:35 UTCApr 28, 09:45 UTC1h 10m
2026-04-27 ASJ02IO - Apr 27, 17:10 UTCApr 27, 18:20 UTC1h 10m
2026-04-27 ASJ02IO ZRH → ZRH Apr 27, 16:30 UTCApr 27, 17:00 UTC30m
2026-04-27 ASJ02IO - Apr 27, 14:55 UTCApr 27, 15:50 UTC55m

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

Mode-S 39990E frequently asked

What is Mode-S code 39990E?
39990E is an ICAO 24-bit transponder address. Allocated to France. Assigned to F-HGIO.
Where is Mode-S 39990E registered?
Mode-S code 39990E is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39990E 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 39990E, octal 16314416, decimal 3,774,734.
What flights does 39990E operate?
Mode-S 39990E has broadcast 1 distinct callsign, including ASJ02IO.