sensors Mode-S transponder

4B3E9F

ICAO 24-bit transponder address · allocated to Switzerland

Currently assigned to HB-XSP · ROBINSON R-44 Raven

Hex
4B3E9F
Octal
22637237
Decimal
4,931,231
Country
CH
Tail
HB-XSP
Type
R44
No current signal · last broadcast 3h ago
Flights observed
5
Distinct callsigns
1
Country
CH
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 4B3E9F.

Country allocation

The ICAO 24-bit address 4B3E9F 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
HBXSP - 5 2026-06-23

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-06-23 HBXSP - Jun 23, 09:54 UTCJun 23, 10:04 UTC10m
2026-05-23 HBXSP - May 23, 16:30 UTCMay 23, 16:40 UTC10m
2026-05-20 HBXSP - May 20, 11:55 UTCMay 20, 12:15 UTC20m
2026-05-20 HBXSP - May 20, 07:05 UTCMay 20, 07:25 UTC20m
2026-05-17 HBXSP - May 17, 08:25 UTCMay 17, 08:40 UTC15m

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

Mode-S 4B3E9F frequently asked

What is Mode-S code 4B3E9F?
4B3E9F is an ICAO 24-bit transponder address. Allocated to Switzerland. Assigned to HB-XSP.
Where is Mode-S 4B3E9F registered?
Mode-S code 4B3E9F is allocated to Switzerland (CH). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B3E9F broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4B3E9F, octal 22637237, decimal 4,931,231.
What flights does 4B3E9F operate?
Mode-S 4B3E9F has broadcast 1 distinct callsign, including HBXSP.