sensors Mode-S transponder

3C70B5

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-ALEU · BOEING 757-200

Hex
3C70B5
Octal
17070265
Decimal
3,961,013
Country
DE
Tail
D-ALEU
Type
B752
Photo of D-ALEU
No current signal · last broadcast 1d ago
Flights observed
2
Distinct callsigns
2
Country
DE
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 3C70B5.

Country allocation

The ICAO 24-bit address 3C70B5 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 2 distinct

Callsign Airline Flights Last seen
BCS4GC - 1 2026-04-13
BCS3LR - 1 2026-04-13

Recent flights last 2

DateFlightRouteTakeoffLandingDuration
2026-04-13 BCS4GC BCN → BRU Apr 13, 20:25 UTCApr 13, 22:20 UTC1h 55m
2026-04-13 BCS3LR LEJ → BCN Apr 13, 00:40 UTCApr 13, 02:45 UTC2h 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-ALEU page for operator, model, and routing details .

Mode-S 3C70B5 frequently asked

What is Mode-S code 3C70B5?
3C70B5 is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-ALEU.
Where is Mode-S 3C70B5 registered?
Mode-S code 3C70B5 is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3C70B5 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 3C70B5, octal 17070265, decimal 3,961,013.
What flights does 3C70B5 operate?
Mode-S 3C70B5 has broadcast 2 distinct callsigns, including BCS4GC, BCS3LR.