sensors Mode-S transponder

3C177A

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-AXXD · AIRBUS A-321neo

Hex
3C177A
Octal
17013572
Decimal
3,938,170
Country
DE
Tail
D-AXXD
Type
A21N
No current signal · last broadcast 19h ago
Flights observed
1
Distinct callsigns
1
Country
DE
Last broadcast
19h ago

Last known position

Most recent position reported by Mode-S 3C177A.

Country allocation

The ICAO 24-bit address 3C177A 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
AIB232C - 1 2026-04-14

Recent flights last 1

DateFlightRouteTakeoffLandingDuration
2026-04-14 AIB232C XFW → XFW Apr 14, 07:45 UTCApr 14, 08:50 UTC1h 5m

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

Mode-S 3C177A frequently asked

What is Mode-S code 3C177A?
3C177A is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-AXXD.
Where is Mode-S 3C177A registered?
Mode-S code 3C177A is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3C177A broadcasting right now?
No active broadcast right now. Last signal was 19h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3C177A, octal 17013572, decimal 3,938,170.
What flights does 3C177A operate?
Mode-S 3C177A has broadcast 1 distinct callsign, including AIB232C.