Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

4B1939

ICAO 24-bit transponder address · allocated to Switzerland

Currently assigned to HB-JOJ · AIRBUS A-319

Hex
4B1939
Octal
22614471
Decimal
4,921,657
Country
CH
Tail
HB-JOJ
Type
A319
No current signal · last broadcast 2h ago
Flights observed
278
Distinct callsigns
20
Country
CH
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 4B1939.

Country allocation

The ICAO 24-bit address 4B1939 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 20 distinct

Callsign Airline Flights Last seen
CSW8GJ - 51 2026-07-11
CSW8HE - 50 2026-07-11
CSW802 - 19 2026-07-13
CSW803 Worldwide Air Charter Systems 18 2026-07-13
CSW805 - 17 2026-07-14
CSW804 - 16 2026-07-14
CSW631 - 12 2026-07-12
CSW638 - 11 2026-06-25
CSW630 - 11 2026-07-12
CSW890 - 9 2026-05-02
CSW639 Worldwide Air Charter Systems 9 2026-06-25
CSW891 - 6 2026-05-02
CSW1PM - 6 2026-07-02
CSW607 Worldwide Air Charter Systems 5 2026-07-11
CSW606 - 5 2026-07-11
CSW1EP - 5 2026-07-02
CSW604 - 4 2026-05-17
CSW605 - 3 2026-05-03
CSW176 - 3 2026-07-13
CSW797 - 2 2026-07-14

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 CSW797 - Jul 14, 17:15 UTCJul 14, 18:55 UTC1h 40m
2026-07-14 CSW796 - Jul 14, 14:10 UTCJul 14, 15:25 UTC1h 15m
2026-07-14 CSW805 - Jul 14, 08:55 UTCJul 14, 11:50 UTC2h 55m
2026-07-14 CSW804 ZRH → KGS Jul 14, 04:55 UTCJul 14, 07:30 UTC2h 35m
2026-07-13 CSW177 OPO → ZRH Jul 13, 18:00 UTCJul 13, 20:05 UTC2h 5m
2026-07-13 CSW176 - Jul 13, 14:10 UTCJul 13, 16:25 UTC2h 15m
2026-07-13 CSW176 - Jul 13, 13:10 UTCJul 13, 13:20 UTC10m
2026-07-13 CSW803 RHO → ZRH Jul 13, 10:00 UTCJul 13, 13:05 UTC3h 5m
2026-07-13 CSW802 ZRH → RHO Jul 13, 06:05 UTCJul 13, 08:40 UTC2h 35m
2026-07-12 CSW631 - Jul 12, 17:35 UTCJul 12, 19:20 UTC1h 45m
2026-07-12 CSW630 - Jul 12, 14:35 UTCJul 12, 16:10 UTC1h 35m
2026-07-12 CSW805 - Jul 12, 10:30 UTCJul 12, 13:20 UTC2h 50m
2026-07-12 CSW804 ZRH → KGS Jul 12, 06:35 UTCJul 12, 09:05 UTC2h 30m
2026-07-11 CSW8HE - Jul 11, 19:00 UTCJul 11, 21:30 UTC2h 30m
2026-07-11 CSW8GJ - Jul 11, 15:20 UTCJul 11, 17:35 UTC2h 15m
2026-07-11 CSW607 PRN → ZRH Jul 11, 11:05 UTCJul 11, 12:50 UTC1h 45m
2026-07-11 CSW606 - Jul 11, 05:55 UTCJul 11, 07:15 UTC1h 20m
2026-07-10 CSW803 RHO → ZRH Jul 10, 17:50 UTCJul 10, 20:45 UTC2h 55m
2026-07-10 CSW802 ZRH → RHO Jul 10, 13:40 UTCJul 10, 16:15 UTC2h 35m
2026-07-10 CSW8HE - Jul 10, 09:45 UTCJul 10, 12:20 UTC2h 35m
2026-07-10 CSW8GJ - Jul 10, 06:05 UTCJul 10, 08:20 UTC2h 15m
2026-07-09 CSW745 - Jul 9, 17:40 UTCJul 9, 19:10 UTC1h 30m
2026-07-09 CSW744 - Jul 9, 15:05 UTCJul 9, 16:15 UTC1h 10m
2026-07-09 CSW797 - Jul 9, 12:30 UTCJul 9, 14:00 UTC1h 30m
2026-07-09 CSW796 - Jul 9, 09:25 UTCJul 9, 10:35 UTC1h 10m
2026-07-08 CSW8HE - Jul 8, 18:30 UTCJul 8, 21:10 UTC2h 40m
2026-07-08 CSW8GJ - Jul 8, 15:00 UTCJul 8, 17:15 UTC2h 15m
2026-07-08 CSW177 OPO → ZRH Jul 8, 10:30 UTCJul 8, 12:45 UTC2h 15m
2026-07-08 CSW176 ZRH → OPO Jul 8, 06:55 UTCJul 8, 09:00 UTC2h 5m
2026-07-07 CSW8HE - Jul 7, 17:55 UTCJul 7, 20:35 UTC2h 40m
2026-07-07 CSW8GJ - Jul 7, 14:25 UTCJul 7, 16:40 UTC2h 15m
2026-07-07 CSW8GJ ZRH → ZRH Jul 7, 13:25 UTCJul 7, 13:30 UTC5m
2026-07-07 CSW805 - Jul 7, 08:35 UTCJul 7, 11:20 UTC2h 45m
2026-07-07 CSW804 ZRH → KGS Jul 7, 05:10 UTCJul 7, 07:35 UTC2h 25m
2026-07-06 CSW8HE - Jul 6, 16:20 UTCJul 6, 19:00 UTC2h 40m
2026-07-06 CSW8GJ - Jul 6, 12:45 UTCJul 6, 15:00 UTC2h 15m
2026-07-06 CSW803 RHO → ZRH Jul 6, 08:30 UTCJul 6, 11:25 UTC2h 55m
2026-07-06 CSW802 ZRH → RHO Jul 6, 04:50 UTCJul 6, 07:20 UTC2h 30m
2026-07-05 CSW445 ZRH → ZRH Jul 5, 09:40 UTCJul 5, 19:05 UTC9h 25m
2026-07-04 CSW8HE - Jul 4, 18:05 UTCJul 4, 20:45 UTC2h 40m
2026-07-04 CSW8GJ - Jul 4, 14:20 UTCJul 4, 16:45 UTC2h 25m
2026-07-04 CSW607 PRN → ZRH Jul 4, 10:55 UTCJul 4, 12:40 UTC1h 45m
2026-07-04 CSW606 - Jul 4, 05:20 UTCJul 4, 06:40 UTC1h 20m
2026-07-03 CSW803 RHO → ZRH Jul 3, 18:05 UTCJul 3, 21:00 UTC2h 55m
2026-07-03 CSW802 - Jul 3, 14:10 UTCJul 3, 16:45 UTC2h 35m
2026-07-03 CSW802 ZRH → ZRH Jul 3, 13:20 UTCJul 3, 13:25 UTC5m
2026-07-03 CSW8HE - Jul 3, 10:00 UTCJul 3, 12:55 UTC2h 55m
2026-07-03 CSW8GJ - Jul 3, 06:20 UTCJul 3, 08:35 UTC2h 15m
2026-07-02 CSW1PM - Jul 2, 12:45 UTCJul 2, 14:20 UTC1h 35m
2026-07-02 CSW1EP - Jul 2, 10:10 UTCJul 2, 11:35 UTC1h 25m

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

Mode-S 4B1939 frequently asked

What is Mode-S code 4B1939?
4B1939 is an ICAO 24-bit transponder address. Allocated to Switzerland. Assigned to HB-JOJ.
Where is Mode-S 4B1939 registered?
Mode-S code 4B1939 is allocated to Switzerland (CH). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B1939 broadcasting right now?
No active broadcast right now. Last signal was 2h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4B1939, octal 22614471, decimal 4,921,657.
What flights does 4B1939 operate?
Mode-S 4B1939 has broadcast 20 distinct callsigns, including CSW8GJ, CSW8HE, CSW802, CSW803, CSW805.