Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

7817B4

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-20DM · BOEING 777-300ER

Hex
7817B4
Octal
36013664
Decimal
7,870,388
Country
CN
Tail
B-20DM
Type
B77W
No current signal · last broadcast 23h ago
Flights observed
78
Distinct callsigns
20
Country
CN
Last broadcast
23h ago

Last known position

Most recent position reported by Mode-S 7817B4.

Country allocation

The ICAO 24-bit address 7817B4 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
CSN3098 China Southern Airlines 10 2026-05-13
CSN3097 China Southern Airlines 7 2026-05-13
CSN328 China Southern Airlines 6 2026-05-23
CSN327 China Southern Airlines 6 2026-05-22
CSN303 China Southern Airlines 6 2026-04-18
CSN348 China Southern Airlines 5 2026-04-29
CSN330 China Southern Airlines 5 2026-05-27
CSN304 China Southern Airlines 5 2026-04-18
CSN660 China Southern Airlines 4 2026-05-01
CSN659 China Southern Airlines 4 2026-04-30
CSN329 China Southern Airlines 3 2026-05-26
CSN312 - 3 2026-04-13
CSN657 China Southern Airlines 2 2026-05-02
CSN386 China Southern Airlines 2 2026-05-25
CSN385 China Southern Airlines 2 2026-05-25
CSN347 China Southern Airlines 2 2026-04-28
CSN311 China Southern Airlines 2 2026-04-13
CSN699 China Southern Airlines 1 2026-05-28
CSN658 China Southern Airlines 1 2026-05-03
CSN3537 China Southern Airlines 1 2026-05-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-28 CSN699 CAN → JFK May 28, 13:00 UTCMay 29, 01:45 UTC12h 45m
2026-05-27 CSN330 YVR → CAN May 27, 20:30 UTCMay 27, 20:40 UTC10m
2026-05-27 CSN330 YVR → CAN May 27, 07:40 UTCMay 27, 18:05 UTC10h 25m
2026-05-26 CSN329 CAN → YVR May 26, 19:30 UTCMay 27, 04:39 UTC9h 10m
2026-05-25 CSN386 HND → CAN May 25, 07:15 UTCMay 25, 08:25 UTC1h 10m
2026-05-25 CSN385 CAN → HND May 25, 04:00 UTCMay 25, 05:20 UTC1h 20m
2026-05-23 CSN328 LAX → CAN May 23, 06:55 UTCMay 23, 18:55 UTC12h 0m
2026-05-22 CSN327 CAN → LAX May 22, 16:40 UTCMay 23, 02:35 UTC9h 54m
2026-05-20 CSN3537 CAN → SHA May 20, 03:25 UTCMay 20, 03:35 UTC10m
2026-05-16 CSN330 YVR → CAN May 16, 16:45 UTCMay 17, 09:55 UTC17h 10m
2026-05-16 CSN330 YVR → CAN May 16, 11:05 UTCMay 17, 09:55 UTC22h 50m
2026-05-16 CSN330 YVR → CAN May 16, 08:01 UTCMay 16, 18:10 UTC10h 10m
2026-05-15 CSN329 CAN → YVR May 15, 19:55 UTCMay 16, 05:00 UTC9h 5m
2026-05-15 CSN329 CAN → YVR May 15, 07:05 UTCMay 16, 05:00 UTC21h 54m
2026-05-14 CSN328 LAX → CAN May 14, 11:15 UTCMay 15, 05:10 UTC17h 55m
2026-05-14 CSN328 LAX → CAN May 14, 07:15 UTCMay 15, 05:10 UTC21h 55m
2026-05-13 CSN327 CAN → LAX May 13, 14:51 UTCMay 14, 02:35 UTC11h 45m
2026-05-13 CSN3098 TPE → CAN May 13, 08:00 UTCMay 13, 08:15 UTC15m
2026-05-13 CSN3098 TPE → CAN May 13, 07:00 UTCMay 13, 07:30 UTC30m
2026-05-13 CSN3097 CAN → TPE May 13, 04:00 UTCMay 13, 05:20 UTC1h 20m
2026-05-12 CSN328 LAX → CAN May 12, 07:10 UTCMay 12, 18:45 UTC11h 35m
2026-05-11 CSN327 CAN → LAX May 11, 16:20 UTCMay 11, 17:40 UTC1h 21m
2026-05-11 CSN3098 TPE → CAN May 11, 07:10 UTCMay 11, 08:25 UTC1h 15m
2026-05-11 CSN3097 CAN → TPE May 11, 03:35 UTCMay 11, 04:50 UTC1h 15m
2026-05-10 CSN3098 TPE → CAN May 10, 07:10 UTCMay 10, 08:30 UTC1h 20m
2026-05-10 CSN3097 CAN → TPE May 10, 03:45 UTCMay 10, 05:04 UTC1h 20m
2026-05-09 CSN386 HND → CAN May 9, 06:55 UTCMay 9, 08:25 UTC1h 30m
2026-05-09 CSN385 CAN → HND May 9, 03:30 UTCMay 9, 04:45 UTC1h 15m
2026-05-03 CSN658 SFO → CAN May 3, 07:40 UTCMay 3, 18:45 UTC11h 5m
2026-05-02 CSN657 HRB → NRT May 2, 17:45 UTCMay 3, 04:00 UTC10h 14m
2026-05-01 CSN657 HRB → NRT May 1, 19:05 UTCMay 2, 19:00 UTC23h 56m
2026-05-01 CSN660 SFO → WUH May 1, 07:45 UTCMay 1, 19:15 UTC11h 30m
2026-04-30 CSN659 WUH → SFO Apr 30, 17:25 UTCMay 1, 03:25 UTC10h 0m
2026-04-30 CSN3098 TPE → CAN Apr 30, 08:20 UTCApr 30, 08:45 UTC25m
2026-04-30 CSN3098 TPE → CAN Apr 30, 07:15 UTCApr 30, 07:45 UTC30m
2026-04-30 CSN3097 CAN → TPE Apr 30, 04:05 UTCApr 30, 05:40 UTC1h 35m
2026-04-29 CSN348 CDG → CAN Apr 29, 10:30 UTCApr 29, 17:05 UTC6h 35m
2026-04-28 CSN347 CAN → CDG Apr 28, 22:10 UTCApr 29, 05:00 UTC6h 50m
2026-04-27 CSN3098 TPE → CAN Apr 27, 06:55 UTCApr 27, 08:00 UTC1h 5m
2026-04-27 CSN3097 CAN → TPE Apr 27, 03:55 UTCApr 27, 05:15 UTC1h 20m
2026-04-25 CSN328 LAX → CAN Apr 25, 07:20 UTCApr 25, 19:05 UTC11h 45m
2026-04-24 CSN327 CAN → LAX Apr 24, 16:10 UTCApr 25, 02:35 UTC10h 25m
2026-04-24 CSN3098 TPE → CAN Apr 24, 08:20 UTCApr 24, 08:30 UTC10m
2026-04-24 CSN3098 TPE → CAN Apr 24, 07:10 UTCApr 24, 07:40 UTC30m
2026-04-24 CSN3097 CAN → TPE Apr 24, 04:15 UTCApr 24, 05:30 UTC1h 15m
2026-04-23 CSN3096 TPE → PVG Apr 23, 12:30 UTCApr 23, 12:40 UTC10m
2026-04-22 CSN348 CDG → CAN Apr 22, 16:15 UTCApr 23, 10:50 UTC18h 35m
2026-04-22 CSN348 CDG → CAN Apr 22, 13:05 UTCApr 23, 10:50 UTC21h 45m
2026-04-22 CSN348 CDG → CAN Apr 22, 11:05 UTCApr 23, 10:50 UTC23h 45m
2026-04-22 CSN348 CDG → CAN Apr 22, 10:25 UTCApr 22, 16:55 UTC6h 30m

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-20DM page for operator, model, and routing details .

Mode-S 7817B4 frequently asked

What is Mode-S code 7817B4?
7817B4 is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-20DM.
Where is Mode-S 7817B4 registered?
Mode-S code 7817B4 is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 7817B4 broadcasting right now?
No active broadcast right now. Last signal was 23h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 7817B4, octal 36013664, decimal 7,870,388.
What flights does 7817B4 operate?
Mode-S 7817B4 has broadcast 20 distinct callsigns, including CSN3098, CSN3097, CSN328, CSN327, CSN303.