Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

781551

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-303L · AIRBUS A-321neo

Hex
781551
Octal
36012521
Decimal
7,869,777
Country
CN
Tail
B-303L
Type
A21N
No current signal · last broadcast Jul 26, 10:20 UTC
Flights observed
92
Distinct callsigns
20
Country
CN
Last broadcast
Jul 26, 10:20 UTC

Last known position

Most recent position reported by Mode-S 781551.

Country allocation

The ICAO 24-bit address 781551 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 20 distinct

Callsign Airline Flights Last seen
CSN672 China Southern Airlines 25 2026-07-24
CSN671 China Southern Airlines 23 2026-07-23
CSN6304 China Southern Airlines 4 2026-07-25
CSN6303 China Southern Airlines 4 2026-07-25
CSN6519 - 3 2026-07-16
CSN6456 China Southern Airlines 3 2026-05-25
CSN6403 - 3 2026-07-18
CSN6414 - 2 2026-06-28
CSN6402 China Southern Airlines 2 2026-07-24
CSN6401 China Southern Airlines 2 2026-05-26
CSN6315 China Southern Airlines 2 2026-05-07
CSN6311 China Southern Airlines 2 2026-05-11
CSN6309 China Southern Airlines 2 2026-06-13
CSN8874 China Southern Airlines 1 2026-07-26
CSN6517 China Southern Airlines 1 2026-04-28
CSN6507 China Southern Airlines 1 2026-05-14
CSN6469 China Southern Airlines 1 2026-05-25
CSN6465 China Southern Airlines 1 2026-07-20
CSN6451 - 1 2026-07-07
CSN6312 China Southern Airlines 1 2026-05-11

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 CSN8874 PKX → SHE Jul 26, 05:20 UTCJul 26, 10:20 UTC5h 1m
2026-07-25 CSN6304 SZX → SHE Jul 25, 16:25 UTCJul 25, 16:40 UTC15m
2026-07-25 CSN6304 SZX → SHE Jul 25, 14:05 UTCJul 25, 14:15 UTC10m
2026-07-25 CSN6303 SHE → SZX Jul 25, 11:55 UTCJul 25, 12:20 UTC25m
2026-07-25 CSN6303 SHE → SZX Jul 25, 08:55 UTCJul 25, 09:10 UTC15m
2026-07-24 CSN672 ICN → SHE Jul 24, 13:10 UTCJul 25, 09:10 UTC20h 0m
2026-07-24 CSN6402 TFU → SHE Jul 24, 07:20 UTCJul 24, 11:45 UTC4h 25m
2026-07-23 CSN672 ICN → SHE Jul 23, 13:00 UTCJul 23, 13:35 UTC35m
2026-07-23 CSN671 SHE → ICN Jul 23, 10:45 UTCJul 23, 11:25 UTC40m
2026-07-22 CSN672 ICN → SHE Jul 22, 13:20 UTCJul 22, 13:55 UTC35m
2026-07-22 CSN671 SHE → ICN Jul 22, 11:10 UTCJul 22, 11:30 UTC20m
2026-07-21 CSN672 ICN → SHE Jul 21, 13:10 UTCJul 21, 13:45 UTC35m
2026-07-21 CSN671 SHE → ICN Jul 21, 10:30 UTCJul 21, 11:25 UTC55m
2026-07-20 CSN671 SHE → ICN Jul 20, 15:00 UTCJul 21, 11:25 UTC20h 24m
2026-07-20 CSN6465 SHE → CKG Jul 20, 01:25 UTCJul 20, 15:10 UTC13h 45m
2026-07-18 CSN672 - Jul 18, 12:55 UTCJul 18, 13:25 UTC30m
2026-07-18 CSN6403 - Jul 18, 01:30 UTCJul 18, 11:10 UTC9h 41m
2026-07-17 CSN672 ICN → ICN Jul 17, 12:50 UTCJul 18, 11:10 UTC22h 21m
2026-07-17 CSN671 - Jul 17, 07:30 UTCJul 17, 11:20 UTC3h 50m
2026-07-16 CSN6519 - Jul 16, 10:25 UTCJul 17, 07:50 UTC21h 25m
2026-07-16 CSN6519 - Jul 16, 10:04 UTCJul 17, 07:50 UTC21h 45m
2026-07-16 CSN6519 - Jul 16, 05:40 UTCJul 16, 10:35 UTC4h 55m
2026-07-08 CSN5811 - Jul 8, 04:20 UTCJul 8, 05:05 UTC45m
2026-07-07 CSN6451 - Jul 7, 01:50 UTCJul 7, 02:35 UTC45m
2026-06-30 CSN6152 CGO → SHE Jun 30, 14:50 UTCJul 1, 04:40 UTC13h 50m
2026-06-28 CSN6414 - Jun 28, 05:34 UTCJun 28, 05:49 UTC15m
2026-06-27 CSN6414 - Jun 27, 06:35 UTCJun 28, 05:49 UTC23h 15m
2026-06-25 CSN6403 - Jun 25, 01:24 UTCJun 25, 10:45 UTC9h 20m
2026-06-24 CSN6403 - Jun 24, 15:35 UTCJun 25, 10:45 UTC19h 10m
2026-06-24 CSN6304 - Jun 24, 13:10 UTCJun 24, 13:24 UTC15m
2026-06-24 CSN6303 - Jun 24, 11:20 UTCJun 24, 11:34 UTC15m
2026-06-24 CSN6303 - Jun 24, 00:59 UTCJun 24, 09:05 UTC8h 5m
2026-06-16 CSN340 - Jun 16, 01:00 UTCJun 16, 01:45 UTC45m
2026-06-15 CSN339 - Jun 15, 12:05 UTCJun 15, 12:39 UTC35m
2026-06-13 CSN6310 SZX → SHE Jun 13, 10:20 UTCJun 13, 10:30 UTC10m
2026-06-13 CSN6309 SHE → SZX Jun 13, 08:00 UTCJun 13, 08:10 UTC10m
2026-06-12 CSN6309 SHE → SZX Jun 12, 12:45 UTCJun 13, 05:25 UTC16h 39m
2026-06-08 CSN672 ICN → SHE Jun 8, 12:55 UTCJun 8, 13:15 UTC20m
2026-06-08 CSN671 SHE → ICN Jun 8, 10:40 UTCJun 8, 11:00 UTC20m
2026-06-07 CSN672 ICN → SHE Jun 7, 13:05 UTCJun 8, 07:40 UTC18h 35m
2026-06-07 CSN671 SHE → ICN Jun 7, 11:00 UTCJun 7, 11:15 UTC15m
2026-06-05 CSN672 ICN → SHE Jun 5, 13:00 UTCJun 6, 08:30 UTC19h 30m
2026-06-05 CSN671 SHE → ICN Jun 5, 10:50 UTCJun 5, 11:20 UTC30m
2026-06-04 CSN672 ICN → SHE Jun 4, 12:55 UTCJun 5, 07:25 UTC18h 30m
2026-06-04 CSN671 SHE → ICN Jun 4, 10:50 UTCJun 4, 11:15 UTC25m
2026-06-03 CSN672 ICN → SHE Jun 3, 13:00 UTCJun 4, 07:45 UTC18h 45m
2026-06-03 CSN671 SHE → ICN Jun 3, 10:50 UTCJun 3, 11:15 UTC25m
2026-06-02 CSN672 ICN → SHE Jun 2, 12:50 UTCJun 3, 07:40 UTC18h 50m
2026-06-02 CSN671 SHE → ICN Jun 2, 10:50 UTCJun 2, 11:10 UTC20m
2026-06-01 CSN672 ICN → SHE Jun 1, 12:55 UTCJun 1, 13:20 UTC25m

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-303L page for operator, model, and routing details .

Mode-S 781551 frequently asked

What is Mode-S code 781551?
781551 is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-303L.
Where is Mode-S 781551 registered?
Mode-S code 781551 is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 781551 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 10:20 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 781551, octal 36012521, decimal 7,869,777.
What flights does 781551 operate?
Mode-S 781551 has broadcast 20 distinct callsigns, including CSN672, CSN671, CSN6304, CSN6303, CSN6519.