sensors Mode-S transponder

4B18D9

ICAO 24-bit transponder address · allocated to Switzerland

Currently assigned to HB-JKR · BOMBARDIER BD-100 Challenger 350

Hex
4B18D9
Octal
22614331
Decimal
4,921,561
Country
CH
Tail
HB-JKR
Type
CL35
No current signal · last broadcast 17d ago
Flights observed
3
Distinct callsigns
1
Country
CH
Last broadcast
17d ago

Last known position

Most recent position reported by Mode-S 4B18D9.

Country allocation

The ICAO 24-bit address 4B18D9 falls within the block assigned to Switzerland (CH) by ICAO Annex 10, Volume III. Every aircraft registered in Switzerland 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
PJZ063 - 3 2026-07-07

Recent flights last 3

DateFlightRouteTakeoffLandingDuration
2026-07-07 PJZ063 RTM → BQH Jul 7, 11:20 UTCJul 7, 12:05 UTC45m
2026-07-07 PJZ063 - Jul 7, 08:15 UTCJul 7, 09:10 UTC55m
2026-07-03 PJZ063 - Jul 3, 07:05 UTCJul 3, 08:15 UTC1h 10m

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 HB-JKR page for operator, model, and routing details .

Mode-S 4B18D9 frequently asked

What is Mode-S code 4B18D9?
4B18D9 is an ICAO 24-bit transponder address. Allocated to Switzerland. Assigned to HB-JKR.
Where is Mode-S 4B18D9 registered?
Mode-S code 4B18D9 is allocated to Switzerland (CH). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B18D9 broadcasting right now?
No active broadcast right now. Last signal was 17d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4B18D9, octal 22614331, decimal 4,921,561.
What flights does 4B18D9 operate?
Mode-S 4B18D9 has broadcast 1 distinct callsign, including PJZ063.