sensors Mode-S transponder

7801A3

ICAO 24-bit transponder address · allocated to China

Currently assigned to B-HYI · AIRBUS A-330-300

Hex
7801A3
Octal
36000643
Decimal
7,864,739
Country
CN
Tail
B-HYI
Type
A333
No current signal · last broadcast 14h ago
Flights observed
153
Distinct callsigns
20
Country
CN
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 7801A3.

Country allocation

The ICAO 24-bit address 7801A3 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
CPA347 Cathay Pacific 7 2026-05-29
CPA654 Cathay Pacific 6 2026-05-02
CPA407 Cathay Pacific 6 2026-05-22
CPA312 Cathay Pacific 6 2026-05-28
CPA780 Cathay Pacific 5 2026-05-23
CPA776 Cathay Pacific 5 2026-05-17
CPA701 Cathay Pacific 5 2026-04-26
CPA653 Cathay Pacific 5 2026-05-02
CPA495 Cathay Pacific 5 2026-05-28
CPA965 Cathay Pacific 4 2026-05-02
CPA783 Cathay Pacific 4 2026-05-03
CPA777 Cathay Pacific 4 2026-05-17
CPA704 Cathay Pacific 4 2026-04-26
CPA691 Cathay Pacific 4 2026-04-27
CPA652 Cathay Pacific 4 2026-04-27
CPA629 Cathay Pacific 4 2026-05-22
CPA597 Cathay Pacific 4 2026-05-25
CPA494 Cathay Pacific 4 2026-05-28
CPA964 Cathay Pacific 3 2026-05-01
CPA782 Cathay Pacific 3 2026-05-03

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 CPA364 HKG → PVG May 29, 10:50 UTCMay 29, 11:00 UTC10m
2026-05-29 CPA364 HKG → PVG May 29, 09:55 UTCMay 29, 10:10 UTC15m
2026-05-29 CPA347 PEK → HKG May 29, 02:25 UTCMay 29, 05:25 UTC3h 0m
2026-05-28 CPA312 HKG → PEK May 28, 09:30 UTCMay 28, 09:50 UTC20m
2026-05-28 CPA495 TPE → HKG May 28, 05:40 UTCMay 28, 06:55 UTC1h 15m
2026-05-28 CPA494 HKG → TPE May 28, 02:25 UTCMay 28, 03:55 UTC1h 30m
2026-05-26 CPA335 PEK → HKG May 26, 04:30 UTCMay 26, 07:29 UTC3h 0m
2026-05-25 CPA334 HKG → PEK May 25, 23:40 UTCMay 26, 00:00 UTC20m
2026-05-25 CPA501 NRT → HKG May 25, 17:15 UTCMay 25, 17:35 UTC20m
2026-05-25 CPA501 NRT → HKG May 25, 13:45 UTCMay 25, 16:45 UTC3h 0m
2026-05-25 CPA500 HKG → NRT May 25, 08:05 UTCMay 25, 12:10 UTC4h 5m
2026-05-25 CPA597 KIX → HKG May 25, 03:30 UTCMay 25, 03:40 UTC10m
2026-05-25 CPA597 KIX → HKG May 25, 02:15 UTCMay 25, 02:55 UTC40m
2026-05-24 CPA566 HKG → KIX May 24, 18:10 UTCMay 24, 21:30 UTC3h 20m
2026-05-23 CPA501 NRT → HKG May 23, 13:15 UTCMay 23, 17:25 UTC4h 10m
2026-05-23 CPA500 HKG → NRT May 23, 07:45 UTCMay 23, 11:30 UTC3h 45m
2026-05-23 CPA780 SUB → HKG May 23, 05:25 UTCMay 23, 05:40 UTC15m
2026-05-22 CPA780 SUB → HKG May 22, 08:50 UTCMay 23, 03:35 UTC18h 44m
2026-05-22 CPA629 HKG → SUB May 22, 06:50 UTCMay 23, 03:35 UTC20h 44m
2026-05-22 CPA407 TPE → HKG May 22, 01:15 UTCMay 22, 01:25 UTC10m
2026-05-22 CPA407 TPE → HKG May 22, 00:15 UTCMay 22, 00:40 UTC25m
2026-05-21 CPA408 HKG → TPE May 21, 15:35 UTCMay 21, 16:55 UTC1h 20m
2026-05-21 CPA724 KUL → HKG May 21, 13:35 UTCMay 21, 13:50 UTC15m
2026-05-21 CPA724 KUL → HKG May 21, 10:20 UTCMay 21, 10:50 UTC30m
2026-05-21 CPA725 HKG → KUL May 21, 08:05 UTCMay 21, 08:50 UTC45m
2026-05-21 CPA725 HKG → KUL May 21, 05:25 UTCMay 21, 05:40 UTC15m
2026-05-21 CPA413 ICN → HKG May 21, 02:15 UTCMay 21, 02:30 UTC15m
2026-05-20 CPA413 ICN → HKG May 20, 23:20 UTCMay 21, 01:35 UTC2h 15m
2026-05-20 CPA430 HKG → ICN May 20, 12:30 UTCMay 20, 13:10 UTC40m
2026-05-20 CPA430 HKG → ICN May 20, 10:45 UTCMay 20, 11:20 UTC35m
2026-05-20 CPA430 HKG → ICN May 20, 09:55 UTCMay 20, 10:10 UTC15m
2026-05-20 CPA349 SHA → HKG May 20, 07:20 UTCMay 20, 07:35 UTC15m
2026-05-20 CPA342 HKG → SHA May 20, 01:50 UTCMay 20, 02:50 UTC1h 0m
2026-05-18 CPA716 SIN → HKG May 18, 13:25 UTCMay 18, 13:35 UTC10m
2026-05-18 CPA716 SIN → HKG May 18, 10:15 UTCMay 18, 10:30 UTC15m
2026-05-18 CPA791 HKG → SIN May 18, 07:10 UTCMay 18, 08:05 UTC55m
2026-05-18 CPA791 HKG → SIN May 18, 04:05 UTCMay 18, 04:20 UTC15m
2026-05-18 CPA407 TPE → HKG May 18, 01:10 UTCMay 18, 01:30 UTC20m
2026-05-18 CPA407 TPE → HKG May 18, 00:05 UTCMay 18, 00:35 UTC30m
2026-05-17 CPA408 HKG → TPE May 17, 15:05 UTCMay 17, 16:20 UTC1h 15m
2026-05-17 CPA776 CGK → HKG May 17, 11:55 UTCMay 17, 12:10 UTC15m
2026-05-17 CPA776 CGK → HKG May 17, 09:25 UTCMay 17, 09:55 UTC30m
2026-05-17 CPA776 CGK → HKG May 17, 07:40 UTCMay 17, 07:50 UTC10m
2026-05-17 CPA777 HKG → CGK May 17, 01:45 UTCMay 17, 02:00 UTC15m
2026-05-09 CPA495 TPE → HKG May 9, 06:30 UTCMay 9, 07:00 UTC30m
2026-05-09 CPA495 TPE → HKG May 9, 05:30 UTCMay 9, 06:00 UTC30m
2026-05-09 CPA494 HKG → TPE May 9, 02:30 UTCMay 9, 03:50 UTC1h 20m
2026-05-08 CPA778 HKT → HKG May 8, 14:35 UTCMay 8, 14:55 UTC20m
2026-05-08 CPA778 HKT → HKG May 8, 08:49 UTCMay 8, 13:15 UTC4h 25m
2026-05-08 CPA773 HKG → HKT May 8, 07:04 UTCMay 8, 07:20 UTC15m

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-HYI page for operator, model, and routing details .

Mode-S 7801A3 frequently asked

What is Mode-S code 7801A3?
7801A3 is an ICAO 24-bit transponder address. Allocated to China. Assigned to B-HYI.
Where is Mode-S 7801A3 registered?
Mode-S code 7801A3 is allocated to China (CN). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 7801A3 broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 7801A3, octal 36000643, decimal 7,864,739.
What flights does 7801A3 operate?
Mode-S 7801A3 has broadcast 20 distinct callsigns, including CPA347, CPA654, CPA407, CPA312, CPA780.