sensors Mode-S transponder

506E21

ICAO 24-bit transponder address · allocated to Slovenia

Currently assigned to S5-DGH · ZLIN Z-43/143

Hex
506E21
Octal
24067041
Decimal
5,271,073
Country
SI
Tail
S5-DGH
Type
Z43
No current signal · last broadcast 28d ago
Flights observed
32
Distinct callsigns
20
Country
SI
Last broadcast
28d ago

Last known position

Most recent position reported by Mode-S 506E21.

Country allocation

The ICAO 24-bit address 506E21 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 20 distinct

Callsign Airline Flights Last seen
WOLF62 - 3 2026-07-20
WOLF55 - 3 2026-07-15
WOLF47 - 3 2026-07-17
WOLF59 - 2 2026-07-14
WOLF58 - 2 2026-07-13
WOLF57 - 2 2026-07-13
WOLF91 - 1 2026-04-23
WOLF80 - 1 2026-07-24
WOLF73 - 1 2026-05-18
WOLF65 - 1 2026-07-20
WOLF64 - 1 2026-07-20
WOLF56 - 1 2026-07-24
WOLF54 - 1 2026-07-14
WOLF53 - 1 2026-07-16
WOLF51 - 1 2026-07-24
WOLF49 - 1 2026-06-15
WOLF41 - 1 2026-06-16
WOLF39 - 1 2026-05-21
WOLF36 - 1 2026-06-09
WOLF21 - 1 2026-06-17

Recent flights last 32

DateFlightRouteTakeoffLandingDuration
2026-07-24 WOLF51 - Jul 24, 10:15 UTCJul 24, 10:45 UTC30m
2026-07-24 WOLF80 - Jul 24, 09:05 UTCJul 24, 09:40 UTC35m
2026-07-24 WOLF56 - Jul 24, 07:50 UTCJul 24, 08:30 UTC40m
2026-07-20 WOLF64 - Jul 20, 11:25 UTCJul 20, 12:00 UTC35m
2026-07-20 WOLF65 - Jul 20, 10:10 UTCJul 20, 10:50 UTC40m
2026-07-20 WOLF62 - Jul 20, 07:55 UTCJul 20, 09:35 UTC1h 40m
2026-07-17 WOLF13 - Jul 17, 09:04 UTCJul 17, 09:55 UTC50m
2026-07-17 WOLF47 - Jul 17, 06:40 UTCJul 17, 07:40 UTC1h 0m
2026-07-16 WOLF53 - Jul 16, 16:55 UTCJul 16, 17:45 UTC50m
2026-07-15 WOLF55 - Jul 15, 08:10 UTCJul 15, 10:55 UTC2h 45m
2026-07-14 WOLF54 - Jul 14, 10:30 UTCJul 14, 11:30 UTC1h 0m
2026-07-14 WOLF59 - Jul 14, 08:55 UTCJul 14, 09:15 UTC20m
2026-07-14 WOLF62 - Jul 14, 06:45 UTCJul 14, 07:30 UTC45m
2026-07-13 WOLF58 - Jul 13, 10:00 UTCJul 13, 11:00 UTC1h 0m
2026-07-13 WOLF55 - Jul 13, 08:35 UTCJul 13, 09:20 UTC45m
2026-07-13 WOLF57 - Jul 13, 07:05 UTCJul 13, 08:01 UTC55m
2026-07-09 WOLF58 - Jul 9, 10:10 UTCJul 9, 10:55 UTC45m
2026-07-09 WOLF59 - Jul 9, 08:40 UTCJul 9, 09:35 UTC55m
2026-07-09 WOLF62 - Jul 9, 07:25 UTCJul 9, 07:55 UTC30m
2026-07-08 WOLF55 - Jul 8, 09:10 UTCJul 8, 10:05 UTC55m
2026-07-08 WOLF57 - Jul 8, 07:20 UTCJul 8, 08:20 UTC1h 0m
2026-06-18 WOLF15 - Jun 18, 17:35 UTCJun 18, 18:45 UTC1h 10m
2026-06-17 WOLF21 - Jun 17, 07:30 UTCJun 17, 10:25 UTC2h 55m
2026-06-16 WOLF11 - Jun 16, 09:40 UTCJun 16, 10:35 UTC55m
2026-06-16 WOLF41 - Jun 16, 08:00 UTCJun 16, 08:44 UTC45m
2026-06-15 WOLF49 - Jun 15, 07:35 UTCJun 15, 08:29 UTC55m
2026-06-09 WOLF36 - Jun 9, 07:15 UTCJun 9, 08:20 UTC1h 5m
2026-05-23 WOLF47 - May 23, 12:20 UTCMay 23, 12:30 UTC10m
2026-05-23 WOLF47 - May 23, 08:10 UTCMay 23, 11:40 UTC3h 30m
2026-05-21 WOLF39 - May 21, 14:15 UTCMay 21, 14:55 UTC40m
2026-05-18 WOLF73 - May 18, 09:00 UTCMay 18, 09:45 UTC45m
2026-04-23 WOLF91 - Apr 23, 14:20 UTCApr 23, 15:35 UTC1h 15m

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

Mode-S 506E21 frequently asked

What is Mode-S code 506E21?
506E21 is an ICAO 24-bit transponder address. Allocated to Slovenia. Assigned to S5-DGH.
Where is Mode-S 506E21 registered?
Mode-S code 506E21 is allocated to Slovenia (SI). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 506E21 broadcasting right now?
No active broadcast right now. Last signal was 28d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 506E21, octal 24067041, decimal 5,271,073.
What flights does 506E21 operate?
Mode-S 506E21 has broadcast 20 distinct callsigns, including WOLF62, WOLF55, WOLF47, WOLF59, WOLF58.