sensors Mode-S transponder

781F24

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-223M · BOEING 757-200

Hex
781F24
Octal
36017444
Decimal
7,872,292
Country
CN
Tail
B-223M
Type
B752
No current signal · last broadcast 1d ago
Flights observed
26
Distinct callsigns
9
Country
CN
Last broadcast
1d ago

Last known position

Most recent position reported by Mode-S 781F24.

Country allocation

The ICAO 24-bit address 781F24 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 9 distinct

Callsign Airline Flights Last seen
CSS142 SF Airlines 6 2026-05-28
CSS280 SF Airlines 5 2026-05-28
CSS279 SF Airlines 5 2026-05-28
CSS141 SF Airlines 4 2026-05-27
CSS7133 - 2 2026-05-28
CSS7278 - 1 2026-04-27
CSS6840 SF Airlines 1 2026-04-27
CSS6839 SF Airlines 1 2026-04-25
CSS6804 SF Airlines 1 2026-04-25

Recent flights last 26

DateFlightRouteTakeoffLandingDuration
2026-05-28 CSS7133 - May 28, 23:15 UTCMay 28, 23:25 UTC10m
2026-05-28 CSS142 ICN → EHU May 28, 14:45 UTCMay 28, 15:05 UTC20m
2026-05-28 CSS279 YNT → ICN May 28, 06:00 UTCMay 28, 06:30 UTC30m
2026-05-28 CSS280 ICN → YNT May 28, 02:55 UTCMay 28, 03:15 UTC20m
2026-05-27 CSS141 EHU → ICN May 27, 23:05 UTCMay 27, 23:25 UTC20m
2026-05-27 CSS142 ICN → EHU May 27, 14:55 UTCMay 27, 15:15 UTC20m
2026-05-27 CSS279 YNT → ICN May 27, 06:15 UTCMay 27, 06:40 UTC25m
2026-05-27 CSS280 ICN → YNT May 27, 03:39 UTCMay 27, 03:59 UTC20m
2026-05-21 CSS142 ICN → EHU May 21, 14:50 UTCMay 21, 15:15 UTC25m
2026-05-21 CSS279 YNT → ICN May 21, 06:05 UTCMay 21, 06:30 UTC25m
2026-05-21 CSS280 ICN → YNT May 21, 03:20 UTCMay 21, 03:40 UTC20m
2026-05-20 CSS141 EHU → ICN May 20, 23:10 UTCMay 20, 23:30 UTC20m
2026-05-18 CSS7133 - May 18, 23:05 UTCMay 18, 23:15 UTC10m
2026-05-11 CSS142 ICN → EHU May 11, 15:00 UTCMay 11, 15:20 UTC20m
2026-05-11 CSS280 ICN → YNT May 11, 03:05 UTCMay 11, 03:15 UTC10m
2026-04-27 CSS7278 - Apr 27, 20:50 UTCApr 27, 21:00 UTC10m
2026-04-27 CSS6840 WUX → SZX Apr 27, 18:50 UTCApr 27, 19:05 UTC15m
2026-04-25 CSS6839 SZX → WUX Apr 25, 22:35 UTCApr 25, 22:45 UTC10m
2026-04-25 CSS6804 EHU → SZX Apr 25, 20:45 UTCApr 25, 21:05 UTC20m
2026-04-20 CSS142 ICN → EHU Apr 20, 14:55 UTCApr 20, 15:10 UTC15m
2026-04-20 CSS279 YNT → ICN Apr 20, 06:00 UTCApr 20, 06:20 UTC20m
2026-04-20 CSS280 ICN → YNT Apr 20, 03:10 UTCApr 20, 03:25 UTC15m
2026-04-18 CSS141 EHU → ICN Apr 18, 23:20 UTCApr 18, 23:40 UTC20m
2026-04-14 CSS142 - Apr 14, 14:50 UTCApr 14, 15:10 UTC20m
2026-04-14 CSS279 YNT → ICN Apr 14, 06:20 UTCApr 14, 06:35 UTC15m
2026-04-13 CSS141 - Apr 13, 23:20 UTCApr 13, 23:40 UTC20m

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-223M page for operator, model, and routing details .

Mode-S 781F24 frequently asked

What is Mode-S code 781F24?
781F24 is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-223M.
Where is Mode-S 781F24 registered?
Mode-S code 781F24 is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 781F24 broadcasting right now?
No active broadcast right now. Last signal was 1d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 781F24, octal 36017444, decimal 7,872,292.
What flights does 781F24 operate?
Mode-S 781F24 has broadcast 9 distinct callsigns, including CSS142, CSS280, CSS279, CSS141, CSS7133.