sensors Mode-S transponder

3E491B

ICAO 24-bit transponder address · allocated to Germany

Currently assigned to D-ISWP · CESSNA 525 Citation M2

Hex
3E491B
Octal
17444433
Decimal
4,081,947
Country
DE
Tail
D-ISWP
Type
C25M
No current signal · last broadcast 2d ago
Flights observed
3
Distinct callsigns
1
Country
DE
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S 3E491B.

Country allocation

The ICAO 24-bit address 3E491B 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
DISWP - 3 2026-04-22

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-04-22 DISWP - Apr 22, 10:20 UTCApr 22, 12:45 UTC2h 25m
2026-04-21 DISWP - Apr 21, 09:15 UTCApr 21, 09:55 UTC40m
2026-04-16 DISWP HAM → MGL Apr 16, 08:04 UTCApr 16, 08:50 UTC45m

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

Mode-S 3E491B frequently asked

What is Mode-S code 3E491B?
3E491B is an ICAO 24-bit transponder address. Allocated to Germany. Assigned to D-ISWP.
Where is Mode-S 3E491B registered?
Mode-S code 3E491B is allocated to Germany (DE). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 3E491B broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 3E491B, octal 17444433, decimal 4,081,947.
What flights does 3E491B operate?
Mode-S 3E491B has broadcast 1 distinct callsign, including DISWP.