Apparatus

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sensors Mode-S transponder

8991A8

ICAO 24-bit transponder address · allocated to Taiwan

Currently assigned to B-18360 · AIRBUS A-330-300

Hex
8991A8
Octal
42310650
Decimal
9,015,720
Country
TW
Tail
B-18360
Type
A333
No current signal · last broadcast 19d ago
Flights observed
279
Distinct callsigns
20
Country
TW
Last broadcast
19d ago

Last known position

Most recent position reported by Mode-S 8991A8.

Country allocation

The ICAO 24-bit address 8991A8 falls within the block assigned to Taiwan (TW) by ICAO Annex 10, Volume III. Every aircraft registered in Taiwan 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
CAL223 China Airlines 47 2026-06-01
CAL221 China Airlines 46 2026-05-31
CAL220 China Airlines 35 2026-05-31
CAL222 China Airlines 32 2026-05-31
CAL201 China Airlines 16 2026-06-01
CAL202 China Airlines 15 2026-06-01
CAL131 - 7 2026-06-20
CAL920 - 6 2026-06-22
CAL919 - 6 2026-06-22
CAL834 - 6 2026-06-24
CAL833 China Airlines 6 2026-06-23
CAL704 - 6 2026-06-23
CAL703 - 5 2026-06-23
CAL130 - 5 2026-06-20
CAL111 China Airlines 4 2026-06-04
CAL173 China Airlines 3 2026-06-04
CAL116 - 3 2026-06-21
CAL172 China Airlines 2 2026-06-04
CAL160 China Airlines 2 2026-06-06
CAL121 - 2 2026-06-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-06-24 CAL834 - Jun 24, 04:15 UTCJun 24, 07:40 UTC3h 25m
2026-06-23 CAL833 TPE → BKK Jun 23, 23:24 UTCJun 24, 02:34 UTC3h 10m
2026-06-23 CAL704 - Jun 23, 09:09 UTCJun 23, 10:55 UTC1h 45m
2026-06-23 CAL703 - Jun 23, 05:39 UTCJun 23, 07:19 UTC1h 40m
2026-06-23 CAL121 - Jun 23, 03:54 UTCJun 23, 04:14 UTC20m
2026-06-23 CAL120 - Jun 23, 00:24 UTCJun 23, 00:50 UTC25m
2026-06-22 CAL920 HKG → TPE Jun 22, 12:25 UTCJun 22, 13:49 UTC1h 25m
2026-06-22 CAL919 TPE → HKG Jun 22, 09:14 UTCJun 22, 10:30 UTC1h 15m
2026-06-22 CAL834 - Jun 22, 04:19 UTCJun 22, 07:40 UTC3h 20m
2026-06-21 CAL833 TPE → BKK Jun 21, 23:24 UTCJun 22, 02:30 UTC3h 5m
2026-06-21 CAL117 - Jun 21, 12:40 UTCJun 21, 14:30 UTC1h 50m
2026-06-21 CAL116 - Jun 21, 10:49 UTCJun 21, 11:05 UTC15m
2026-06-21 CAL116 - Jun 21, 09:29 UTCJun 21, 09:59 UTC30m
2026-06-21 CAL834 - Jun 21, 04:10 UTCJun 21, 07:40 UTC3h 30m
2026-06-20 CAL833 TPE → BKK Jun 20, 23:19 UTCJun 21, 02:24 UTC3h 5m
2026-06-20 CAL131 - Jun 20, 09:49 UTCJun 20, 10:09 UTC20m
2026-06-20 CAL131 - Jun 20, 06:24 UTCJun 20, 08:29 UTC2h 5m
2026-06-20 CAL130 TPE → CTS Jun 20, 01:05 UTCJun 20, 04:34 UTC3h 30m
2026-06-19 CAL131 - Jun 19, 06:39 UTCJun 19, 08:44 UTC2h 5m
2026-06-19 CAL130 - Jun 19, 02:29 UTCJun 19, 04:50 UTC2h 20m
2026-06-19 CAL130 - Jun 19, 01:10 UTCJun 19, 01:24 UTC15m
2026-06-18 CAL704 - Jun 18, 09:20 UTCJun 18, 11:00 UTC1h 40m
2026-06-18 CAL703 TPE → MNL Jun 18, 05:40 UTCJun 18, 07:35 UTC1h 55m
2026-06-17 CAL704 - Jun 17, 09:10 UTCJun 17, 10:50 UTC1h 40m
2026-06-17 CAL703 - Jun 17, 05:50 UTCJun 17, 07:40 UTC1h 50m
2026-06-17 CAL121 - Jun 17, 00:35 UTCJun 17, 04:30 UTC3h 55m
2026-06-16 CAL834 - Jun 16, 05:45 UTCJun 16, 09:20 UTC3h 35m
2026-06-16 CAL833 TPE → BKK Jun 16, 00:55 UTCJun 16, 04:10 UTC3h 15m
2026-06-15 CAL792 - Jun 15, 05:00 UTCJun 15, 07:29 UTC2h 30m
2026-06-15 CAL791 - Jun 15, 00:35 UTCJun 15, 03:05 UTC2h 30m
2026-06-14 CAL832 BKK → TPE Jun 14, 06:40 UTCJun 14, 10:40 UTC4h 0m
2026-06-14 CAL831 - Jun 14, 02:00 UTCJun 14, 05:05 UTC3h 5m
2026-06-13 CAL704 MNL → TPE Jun 13, 20:00 UTCJun 13, 21:40 UTC1h 40m
2026-06-13 CAL2703 TPE → MNL Jun 13, 16:25 UTCJun 13, 18:20 UTC1h 55m
2026-06-13 CAL131 CTS → TPE Jun 13, 10:05 UTCJun 13, 10:30 UTC25m
2026-06-13 CAL131 CTS → TPE Jun 13, 06:45 UTCJun 13, 08:40 UTC1h 55m
2026-06-13 CAL130 - Jun 13, 01:10 UTCJun 13, 04:25 UTC3h 15m
2026-06-12 CAL131 CTS → TPE Jun 12, 10:00 UTCJun 12, 10:30 UTC30m
2026-06-12 CAL131 CTS → TPE Jun 12, 06:30 UTCJun 12, 08:30 UTC2h 0m
2026-06-12 CAL130 - Jun 12, 00:55 UTCJun 12, 04:10 UTC3h 15m
2026-06-11 CAL836 BKK → TPE Jun 11, 11:00 UTCJun 11, 14:15 UTC3h 15m
2026-06-11 CAL835 TPE → BKK Jun 11, 05:45 UTCJun 11, 09:00 UTC3h 15m
2026-06-10 CAL153 KIX → TPE Jun 10, 05:45 UTCJun 10, 08:25 UTC2h 40m
2026-06-10 CAL152 TPE → KIX Jun 10, 01:40 UTCJun 10, 03:40 UTC2h 0m
2026-06-09 CAL920 HKG → TPE Jun 9, 13:15 UTCJun 9, 14:30 UTC1h 15m
2026-06-09 CAL919 TPE → HKG Jun 9, 10:45 UTCJun 9, 11:00 UTC15m
2026-06-09 CAL919 TPE → HKG Jun 9, 09:35 UTCJun 9, 10:05 UTC30m
2026-06-09 CAL552 CTU → TPE Jun 9, 00:50 UTCJun 9, 08:15 UTC7h 25m
2026-06-08 CAL105 NRT → TPE Jun 8, 12:10 UTCJun 8, 12:35 UTC25m
2026-06-08 CAL105 NRT → TPE Jun 8, 09:20 UTCJun 8, 10:45 UTC1h 25m

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-18360 page for operator, model, and routing details .

Mode-S 8991A8 frequently asked

What is Mode-S code 8991A8?
8991A8 is an ICAO 24-bit transponder address. Allocated to Taiwan. Assigned to B-18360.
Where is Mode-S 8991A8 registered?
Mode-S code 8991A8 is allocated to Taiwan (TW). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8991A8 broadcasting right now?
No active broadcast right now. Last signal was 19d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8991A8, octal 42310650, decimal 9,015,720.
What flights does 8991A8 operate?
Mode-S 8991A8 has broadcast 20 distinct callsigns, including CAL223, CAL221, CAL220, CAL222, CAL201.