sensors Mode-S transponder

4B1A23

ICAO 24-bit transponder address · allocated to Switzerland

Currently assigned to HB-JXJ · AIRBUS A-320

Hex
4B1A23
Octal
22615043
Decimal
4,921,891
Country
CH
Tail
HB-JXJ
Type
A320
Photo of HB-JXJ
No current signal · last broadcast 12h ago
Flights observed
17
Distinct callsigns
10
Country
CH
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S 4B1A23.

Country allocation

The ICAO 24-bit address 4B1A23 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 10 distinct

Callsign Airline Flights Last seen
EZS37YZ - 3 2026-04-13
EZS1523 - 3 2026-04-13
EZS63BD - 2 2026-04-14
EZS35JU - 2 2026-04-13
EZS34ML - 2 2026-04-13
EZS79YP Easyjet Switzerland 1 2026-04-14
EZS27FR - 1 2026-04-13
EZS1369 Easyjet Switzerland 1 2026-04-13
EJU96UW - 1 2026-04-12
EJU73ZQ - 1 2026-04-12

Recent flights last 17

DateFlightRouteTakeoffLandingDuration
2026-04-14 EZS63BD - Apr 14, 09:10 UTCApr 14, 10:30 UTC1h 20m
2026-04-14 EZS63BD - Apr 14, 08:20 UTCApr 14, 09:05 UTC45m
2026-04-14 EZS79YP GVA → LIS Apr 14, 05:15 UTCApr 14, 06:50 UTC1h 35m
2026-04-13 EZS35JU - Apr 13, 19:50 UTCApr 13, 20:20 UTC30m
2026-04-13 EZS35JU - Apr 13, 19:15 UTCApr 13, 20:10 UTC55m
2026-04-13 EZS27FR - Apr 13, 17:20 UTCApr 13, 18:25 UTC1h 5m
2026-04-13 EZS37YZ - Apr 13, 16:15 UTCApr 13, 16:30 UTC15m
2026-04-13 EZS37YZ - Apr 13, 15:50 UTCApr 13, 16:30 UTC40m
2026-04-13 EZS37YZ - Apr 13, 14:05 UTCApr 13, 16:15 UTC2h 10m
2026-04-13 EZS1523 - Apr 13, 12:20 UTCApr 13, 13:00 UTC40m
2026-04-13 EZS1523 - Apr 13, 11:55 UTCApr 13, 13:00 UTC1h 5m
2026-04-13 EZS1523 - Apr 13, 10:55 UTCApr 13, 12:15 UTC1h 20m
2026-04-13 EZS34ML - Apr 13, 08:20 UTCApr 13, 09:50 UTC1h 30m
2026-04-13 EZS34ML - Apr 13, 08:00 UTCApr 13, 08:15 UTC15m
2026-04-13 EZS1369 GVA → LCG Apr 13, 04:55 UTCApr 13, 06:55 UTC2h 0m
2026-04-12 EJU96UW - Apr 12, 19:50 UTCApr 12, 20:15 UTC25m
2026-04-12 EJU73ZQ - Apr 12, 17:15 UTCApr 12, 18:40 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-JXJ page for operator, model, and routing details .

Mode-S 4B1A23 frequently asked

What is Mode-S code 4B1A23?
4B1A23 is an ICAO 24-bit transponder address. Allocated to Switzerland. Assigned to HB-JXJ.
Where is Mode-S 4B1A23 registered?
Mode-S code 4B1A23 is allocated to Switzerland (CH). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 4B1A23 broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 4B1A23, octal 22615043, decimal 4,921,891.
What flights does 4B1A23 operate?
Mode-S 4B1A23 has broadcast 10 distinct callsigns, including EZS37YZ, EZS1523, EZS63BD, EZS35JU, EZS34ML.