sensors Mode-S transponder

3CD55C

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-CICI · CESSNA 560XL Citation XLS

Hex
3CD55C
Octal
17152534
Decimal
3,986,780
Country
DE
Tail
D-CICI
Type
C56X
No current signal · last broadcast 1d ago
Flights observed
4
Distinct callsigns
1
Country
DE
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 3CD55C.

Country allocation

The ICAO 24-bit address 3CD55C 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 1 distinct

Callsign Airline Flights Last seen
DCS603 - 4 2026-04-14

Recent flights last 4

DateFlightRouteTakeoffLandingDuration
2026-04-14 DCS603 - Apr 14, 07:10 UTCApr 14, 07:30 UTC20m
2026-04-14 DCS603 - Apr 14, 06:00 UTCApr 14, 06:35 UTC35m
2026-04-13 DCS603 - Apr 13, 15:05 UTCApr 13, 15:55 UTC50m
2026-04-13 DCS603 - Apr 13, 13:15 UTCApr 13, 14:15 UTC1h 0m

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 D-CICI page for operator, model, and routing details .

Mode-S 3CD55C frequently asked

What is Mode-S code 3CD55C?
3CD55C is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-CICI.
Where is Mode-S 3CD55C registered?
Mode-S code 3CD55C is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3CD55C broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3CD55C, octal 17152534, decimal 3,986,780.
What flights does 3CD55C operate?
Mode-S 3CD55C has broadcast 1 distinct callsign, including DCS603.