sensors Mode-S transponder

39DD05

ICAO 24-bit transponder address · allocated to France

Hex
39DD05
Octal
16356405
Decimal
3,792,133
Country
FR
Broadcasting now · callsign TVF591U · 37,000 ft
Flights observed
5
Distinct callsigns
5
Country
FR
Last broadcast
2h ago

Current position

39DD05 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 39DD05 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 5 distinct

Callsign Airline Flights Last seen
TVF739F - 1 2026-06-27
TVF68FN - 1 2026-06-27
TVF431J - 1 2026-06-26
TVF30QP - 1 2026-06-26
TVF251 - 1 2026-06-23

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-27 TVF739F MAH → ORY Jun 27, 07:15 UTCJun 27, 08:44 UTC1h 30m
2026-06-27 TVF68FN ORY → MAH Jun 27, 04:34 UTCJun 27, 06:05 UTC1h 30m
2026-06-26 TVF431J CPH → ORY Jun 26, 17:44 UTCJun 26, 19:30 UTC1h 45m
2026-06-26 TVF30QP ORY → CPH Jun 26, 15:10 UTCJun 26, 16:44 UTC1h 35m
2026-06-23 TVF251 TLS → ORY Jun 23, 20:10 UTCJun 23, 21:05 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.

Mode-S 39DD05 frequently asked

What is Mode-S code 39DD05?
39DD05 is an ICAO 24-bit transponder address. Allocated to France.
Where is Mode-S 39DD05 registered?
Mode-S code 39DD05 is allocated to France (FR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 39DD05 broadcasting right now?
Yes. Mode-S 39DD05 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 39DD05, octal 16356405, decimal 3,792,133.
What flights does 39DD05 operate?
Mode-S 39DD05 has broadcast 5 distinct callsigns, including TVF739F, TVF68FN, TVF431J, TVF30QP, TVF251.