sensors Mode-S transponder

3D124C

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-EFEI · DIAMOND DA-40 Club Star

Hex
3D124C
Octal
17211114
Decimal
4,002,380
Country
DE
Tail
D-EFEI
Type
DA40
No current signal · last broadcast 20h ago
Flights observed
7
Distinct callsigns
4
Country
DE
Last broadcast
20h ago

Last known position

Most recent position reported by Mode-S 3D124C.

Country allocation

The ICAO 24-bit address 3D124C 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
OCO434N - 3 2026-04-13
OCO435S - 2 2026-04-13
OCO331E - 1 2026-04-14
OCO113P - 1 2026-04-14

Recent flights last 7

DateFlightRouteTakeoffLandingDuration
2026-04-14 OCO331E - Apr 14, 10:05 UTCApr 14, 11:05 UTC1h 0m
2026-04-14 OCO113P - Apr 14, 07:30 UTCApr 14, 07:55 UTC25m
2026-04-13 OCO435S - Apr 13, 11:55 UTCApr 13, 12:25 UTC30m
2026-04-13 OCO435S - Apr 13, 10:25 UTCApr 13, 12:15 UTC1h 50m
2026-04-13 OCO434N - Apr 13, 08:20 UTCApr 13, 09:00 UTC40m
2026-04-13 OCO434N - Apr 13, 07:55 UTCApr 13, 09:00 UTC1h 5m
2026-04-13 OCO434N - Apr 13, 07:10 UTCApr 13, 08:15 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-EFEI page for operator, model, and routing details .

Mode-S 3D124C frequently asked

What is Mode-S code 3D124C?
3D124C is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-EFEI.
Where is Mode-S 3D124C registered?
Mode-S code 3D124C is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3D124C broadcasting right now?
No active broadcast right now. Last signal was 20h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3D124C, octal 17211114, decimal 4,002,380.
What flights does 3D124C operate?
Mode-S 3D124C has broadcast 4 distinct callsigns, including OCO434N, OCO435S, OCO331E, OCO113P.