sensors Mode-S transponder

506D8E

ICAO 24-bit transponder address · allocated to Slovenia

Currently assigned to S5-CES · CESSNA 525B Citation CJ3

Hex
506D8E
Octal
24066616
Decimal
5,270,926
Country
SI
Tail
S5-CES
Type
C25B
No current signal · last broadcast 1d ago
Flights observed
6
Distinct callsigns
1
Country
SI
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 506D8E.

Country allocation

The ICAO 24-bit address 506D8E falls within the block assigned to Slovenia (SI) by ICAO Annex 10, Volume III. Every aircraft registered in Slovenia 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
UEE1 - 6 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-13 UEE1 - Apr 13, 19:50 UTCApr 13, 20:25 UTC35m
2026-04-13 UEE1 - Apr 13, 19:35 UTCApr 13, 19:45 UTC10m
2026-04-13 UEE1 - Apr 13, 14:05 UTCApr 13, 14:55 UTC50m
2026-04-13 UEE1 - Apr 13, 12:20 UTCApr 13, 12:40 UTC20m
2026-04-13 UEE1 - Apr 13, 11:55 UTCApr 13, 12:40 UTC45m
2026-04-13 UEE1 - Apr 13, 11:40 UTCApr 13, 12:15 UTC35m

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 S5-CES page for operator, model, and routing details .

Mode-S 506D8E frequently asked

What is Mode-S code 506D8E?
506D8E is an ICAO 24-bit transponder address. Allocated to Slovenia. Assigned to S5-CES.
Where is Mode-S 506D8E registered?
Mode-S code 506D8E is allocated to Slovenia (SI). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 506D8E 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 506D8E, octal 24066616, decimal 5,270,926.
What flights does 506D8E operate?
Mode-S 506D8E has broadcast 1 distinct callsign, including UEE1.