sensors Mode-S transponder

3DD65F

ICAO 24-bit transponder address · allocated to Germany

Hex
3DD65F
Octal
17353137
Decimal
4,052,575
Country
DE
No current signal · last broadcast 1h ago
Flights observed
5
Distinct callsigns
4
Country
DE
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 3DD65F.

Country allocation

The ICAO 24-bit address 3DD65F falls within the block assigned to Germany (DE) by ICAO Annex 10, Volume III. Every aircraft registered in Germany 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 4 distinct

Callsign Airline Flights Last seen
RDF29 - 2 2026-06-25
RDF27 - 1 2026-06-22
RDF25 - 1 2026-06-23
RDF15 - 1 2026-06-24

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-25 RDF29 - Jun 25, 09:05 UTCJun 25, 09:40 UTC35m
2026-06-24 RDF15 - Jun 24, 12:20 UTCJun 24, 12:50 UTC30m
2026-06-23 RDF25 - Jun 23, 07:55 UTCJun 23, 08:54 UTC1h 0m
2026-06-22 RDF27 - Jun 22, 12:10 UTCJun 22, 12:49 UTC40m
2026-06-19 RDF29 - Jun 19, 11:39 UTCJun 19, 11:59 UTC20m

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 3DD65F frequently asked

What is Mode-S code 3DD65F?
3DD65F is an ICAO 24-bit transponder address. Allocated to Germany.
Where is Mode-S 3DD65F registered?
Mode-S code 3DD65F is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3DD65F broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3DD65F, octal 17353137, decimal 4,052,575.
What flights does 3DD65F operate?
Mode-S 3DD65F has broadcast 4 distinct callsigns, including RDF29, RDF27, RDF25, RDF15.