sensors Mode-S transponder

3C66AC

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-AIUL · AIRBUS A-320

Hex
3C66AC
Octal
17063254
Decimal
3,958,444
Country
DE
Tail
D-AIUL
Type
A320
No current signal · last broadcast 2h ago
Flights observed
6
Distinct callsigns
6
Country
DE
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 3C66AC.

Country allocation

The ICAO 24-bit address 3C66AC 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 6 distinct

Callsign Airline Flights Last seen
DLH9XC - 1 2026-04-18
DLH6YW Lufthansa 1 2026-04-18
DLH6CJ - 1 2026-04-18
DLH4UV Lufthansa 1 2026-04-18
DLH2RX - 1 2026-04-18
DLH1KX - 1 2026-04-18

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-18 DLH2RX - Apr 18, 18:25 UTCApr 18, 19:30 UTC1h 5m
2026-04-18 DLH6CJ - Apr 18, 15:25 UTCApr 18, 16:50 UTC1h 25m
2026-04-18 DLH9XC - Apr 18, 13:00 UTCApr 18, 14:05 UTC1h 5m
2026-04-18 DLH1KX - Apr 18, 09:55 UTCApr 18, 11:30 UTC1h 35m
2026-04-18 DLH6YW FRA → HAM Apr 18, 07:25 UTCApr 18, 09:00 UTC1h 35m
2026-04-18 DLH4UV FRA → BLQ Apr 18, 05:30 UTCApr 18, 06:25 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 D-AIUL page for operator, model, and routing details .

Mode-S 3C66AC frequently asked

What is Mode-S code 3C66AC?
3C66AC is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-AIUL.
Where is Mode-S 3C66AC registered?
Mode-S code 3C66AC is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3C66AC 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 3C66AC, octal 17063254, decimal 3,958,444.
What flights does 3C66AC operate?
Mode-S 3C66AC has broadcast 6 distinct callsigns, including DLH9XC, DLH6YW, DLH6CJ, DLH4UV, DLH2RX.