sensors Mode-S transponder

3D2491

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-EMCF · CESSNA 172 Skyhawk

Hex
3D2491
Octal
17222221
Decimal
4,007,057
Country
DE
Tail
D-EMCF
Type
C172
No current signal · last broadcast 5h ago
Flights observed
18
Distinct callsigns
1
Country
DE
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S 3D2491.

Country allocation

The ICAO 24-bit address 3D2491 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
DEMCF - 18 2026-04-18

Recent flights last 18

DateFlightRouteTakeoffLandingDuration
2026-04-18 DEMCF - Apr 18, 16:30 UTCApr 18, 17:35 UTC1h 5m
2026-04-18 DEMCF - Apr 18, 09:20 UTCApr 18, 10:35 UTC1h 15m
2026-04-17 DEMCF - Apr 17, 15:20 UTCApr 17, 15:55 UTC35m
2026-04-17 DEMCF - Apr 17, 15:00 UTCApr 17, 15:15 UTC15m
2026-04-17 DEMCF - Apr 17, 10:55 UTCApr 17, 11:05 UTC10m
2026-04-17 DEMCF - Apr 17, 09:50 UTCApr 17, 10:10 UTC20m
2026-04-16 DEMCF - Apr 16, 17:15 UTCApr 16, 17:40 UTC25m
2026-04-16 DEMCF - Apr 16, 16:50 UTCApr 16, 17:10 UTC20m
2026-04-16 DEMCF - Apr 16, 15:20 UTCApr 16, 15:35 UTC15m
2026-04-16 DEMCF - Apr 16, 13:50 UTCApr 16, 14:45 UTC55m
2026-04-16 DEMCF - Apr 16, 12:19 UTCApr 16, 13:00 UTC40m
2026-04-16 DEMCF - Apr 16, 11:09 UTCApr 16, 11:39 UTC30m
2026-04-16 DEMCF - Apr 16, 10:54 UTCApr 16, 11:04 UTC10m
2026-04-16 DEMCF - Apr 16, 09:29 UTCApr 16, 09:59 UTC30m
2026-04-14 DEMCF - Apr 14, 14:50 UTCApr 14, 15:15 UTC25m
2026-04-14 DEMCF - Apr 14, 14:30 UTCApr 14, 14:45 UTC15m
2026-04-13 DEMCF - Apr 13, 14:40 UTCApr 13, 15:15 UTC35m
2026-04-13 DEMCF - Apr 13, 13:15 UTCApr 13, 13:45 UTC30m

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

Mode-S 3D2491 frequently asked

What is Mode-S code 3D2491?
3D2491 is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-EMCF.
Where is Mode-S 3D2491 registered?
Mode-S code 3D2491 is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3D2491 broadcasting right now?
No active broadcast right now. Last signal was 5h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3D2491, octal 17222221, decimal 4,007,057.
What flights does 3D2491 operate?
Mode-S 3D2491 has broadcast 1 distinct callsign, including DEMCF.