sensors Mode-S transponder

4B2939

ICAO 24-bit transponder address · allocated to Switzerland

Currently assigned to HB-PPX · PIPER PA-28-140/150/160/180

Hex
4B2939
Octal
22624471
Decimal
4,925,753
Country
CH
Tail
HB-PPX
Type
P28A
No current signal · last broadcast 21h ago
Flights observed
35
Distinct callsigns
1
Country
CH
Last broadcast
21h ago

Last known position

Most recent position reported by Mode-S 4B2939.

Country allocation

The ICAO 24-bit address 4B2939 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
HBPPX - 35 2026-05-29

Recent flights last 35

DateFlightRouteTakeoffLandingDuration
2026-05-29 HBPPX - May 29, 17:45 UTCMay 29, 18:10 UTC25m
2026-05-19 HBPPX - May 19, 16:40 UTCMay 19, 17:05 UTC25m
2026-05-19 HBPPX - May 19, 13:10 UTCMay 19, 14:35 UTC1h 25m
2026-05-18 HBPPX - May 18, 09:55 UTCMay 18, 11:15 UTC1h 20m
2026-05-13 HBPPX - May 13, 14:40 UTCMay 13, 15:05 UTC25m
2026-05-13 HBPPX - May 13, 12:40 UTCMay 13, 14:00 UTC1h 20m
2026-05-13 HBPPX - May 13, 11:00 UTCMay 13, 11:35 UTC35m
2026-05-13 HBPPX - May 13, 09:40 UTCMay 13, 10:25 UTC45m
2026-05-13 HBPPX - May 13, 08:05 UTCMay 13, 08:45 UTC40m
2026-05-08 HBPPX - May 8, 05:44 UTCMay 8, 06:09 UTC25m
2026-05-05 HBPPX ACH → ACH May 5, 09:00 UTCMay 5, 09:55 UTC55m
2026-04-30 HBPPX - Apr 30, 15:00 UTCApr 30, 16:15 UTC1h 15m
2026-04-30 HBPPX - Apr 30, 09:50 UTCApr 30, 10:55 UTC1h 5m
2026-04-26 HBPPX - Apr 26, 12:40 UTCApr 26, 15:05 UTC2h 25m
2026-04-26 HBPPX - Apr 26, 10:50 UTCApr 26, 12:05 UTC1h 15m
2026-04-26 HBPPX - Apr 26, 08:25 UTCApr 26, 09:30 UTC1h 5m
2026-04-25 HBPPX - Apr 25, 13:35 UTCApr 25, 15:05 UTC1h 30m
2026-04-25 HBPPX - Apr 25, 10:45 UTCApr 25, 12:20 UTC1h 35m
2026-04-25 HBPPX - Apr 25, 07:20 UTCApr 25, 09:50 UTC2h 30m
2026-04-18 HBPPX - Apr 18, 12:05 UTCApr 18, 12:25 UTC20m
2026-04-18 HBPPX - Apr 18, 09:30 UTCApr 18, 09:45 UTC15m
2026-04-16 HBPPX ACH → ACH Apr 16, 13:54 UTCApr 16, 14:40 UTC45m
2026-04-16 HBPPX ACH → ACH Apr 16, 11:35 UTCApr 16, 12:19 UTC45m
2026-04-16 HBPPX ACH → ACH Apr 16, 07:19 UTCApr 16, 08:09 UTC50m
2026-04-15 HBPPX - Apr 15, 15:05 UTCApr 15, 15:55 UTC50m
2026-04-15 HBPPX - Apr 15, 13:01 UTCApr 15, 14:35 UTC1h 35m
2026-04-15 HBPPX - Apr 15, 12:45 UTCApr 15, 12:55 UTC10m
2026-04-15 HBPPX - Apr 15, 11:35 UTCApr 15, 12:15 UTC40m
2026-04-15 HBPPX - Apr 15, 08:35 UTCApr 15, 08:55 UTC20m
2026-04-15 HBPPX - Apr 15, 07:01 UTCApr 15, 07:30 UTC30m
2026-04-14 HBPPX ACH → ACH Apr 14, 13:00 UTCApr 14, 14:45 UTC1h 45m
2026-04-14 HBPPX ACH → ACH Apr 14, 11:50 UTCApr 14, 12:35 UTC45m
2026-04-13 HBPPX ACH → ACH Apr 13, 13:35 UTCApr 13, 14:30 UTC55m
2026-04-13 HBPPX ACH → ACH Apr 13, 12:40 UTCApr 13, 13:05 UTC25m
2026-04-13 HBPPX ACH → ACH Apr 13, 12:00 UTCApr 13, 12:15 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-PPX page for operator, model, and routing details .

Mode-S 4B2939 frequently asked

What is Mode-S code 4B2939?
4B2939 is an ICAO 24-bit transponder address. Allocated to Switzerland. Assigned to HB-PPX.
Where is Mode-S 4B2939 registered?
Mode-S code 4B2939 is allocated to Switzerland (CH). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B2939 broadcasting right now?
No active broadcast right now. Last signal was 21h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4B2939, octal 22624471, decimal 4,925,753.
What flights does 4B2939 operate?
Mode-S 4B2939 has broadcast 1 distinct callsign, including HBPPX.