sensors Mode-S transponder

781125

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-1409 · BOEING 737-800

Hex
781125
Octal
36010445
Decimal
7,868,709
Country
CN
Tail
B-1409
Type
B738
No current signal · last broadcast 12h ago
Flights observed
5
Distinct callsigns
5
Country
CN
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S 781125.

Country allocation

The ICAO 24-bit address 781125 falls within the block assigned to China (CN) by ICAO Annex 10, Volume III. Every aircraft registered in China 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 5 distinct

Callsign Airline Flights Last seen
CSN6706 - 1 2026-04-13
CSN6705 China Southern Airlines 1 2026-04-13
CSN3674 - 1 2026-04-13
CSN3673 - 1 2026-04-13
CSN3647 - 1 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 CSN3647 - Apr 14, 10:35 UTCApr 14, 10:50 UTC15m
2026-04-13 CSN3673 - Apr 13, 09:15 UTCApr 13, 09:25 UTC10m
2026-04-13 CSN6706 - Apr 13, 07:05 UTCApr 13, 07:20 UTC15m
2026-04-13 CSN6705 SZX → WMT Apr 13, 03:00 UTCApr 13, 03:10 UTC10m
2026-04-13 CSN3674 - Apr 13, 01:15 UTCApr 13, 01:25 UTC10m

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 B-1409 page for operator, model, and routing details .

Mode-S 781125 frequently asked

What is Mode-S code 781125?
781125 is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-1409.
Where is Mode-S 781125 registered?
Mode-S code 781125 is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 781125 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 781125, octal 36010445, decimal 7,868,709.
What flights does 781125 operate?
Mode-S 781125 has broadcast 5 distinct callsigns, including CSN6706, CSN6705, CSN3674, CSN3673, CSN3647.