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sensors Mode-S transponder

8991B5

ICAO 24-bit transponder address · allocated to Taiwan

Currently assigned to B-18307 · AIRBUS A-330-300

Hex
8991B5
Octal
42310665
Decimal
9,015,733
Country
TW
Tail
B-18307
Type
A333
Broadcasting now · callsign MDA991 · 18,900 ft
Flights observed
177
Distinct callsigns
20
Country
TW
Last broadcast
11h ago

Current position

8991B5 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 8991B5 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
CAL161 China Airlines 12 2026-05-25
CAL117 China Airlines 11 2026-05-29
CAL163 China Airlines 10 2026-05-25
CAL116 China Airlines 9 2026-05-29
CAL835 China Airlines 8 2026-05-15
CAL162 China Airlines 8 2026-05-25
CAL836 China Airlines 7 2026-05-15
CAL791 China Airlines 7 2026-05-29
CAL160 China Airlines 7 2026-05-25
CAL792 China Airlines 6 2026-05-28
CAL131 China Airlines 6 2026-05-12
CAL157 China Airlines 5 2026-05-27
CAL923 China Airlines 4 2026-05-17
CAL834 China Airlines 4 2026-05-26
CAL702 China Airlines 4 2026-05-18
CAL528 China Airlines 4 2026-05-22
CAL173 China Airlines 4 2026-05-18
CAL151 China Airlines 4 2026-04-24
CAL130 China Airlines 4 2026-05-12
CAL111 China Airlines 4 2026-05-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 CAL117 FUK → TPE May 29, 13:45 UTCMay 29, 14:20 UTC35m
2026-05-29 CAL116 TPE → FUK May 29, 08:50 UTCMay 29, 09:15 UTC25m
2026-05-29 CAL791 TPE → HAN May 29, 00:45 UTCMay 29, 07:20 UTC6h 35m
2026-05-28 CAL117 FUK → TPE May 28, 14:10 UTCMay 28, 14:25 UTC15m
2026-05-28 CAL116 TPE → FUK May 28, 10:50 UTCMay 28, 11:00 UTC10m
2026-05-28 CAL116 TPE → FUK May 28, 09:10 UTCMay 28, 09:30 UTC20m
2026-05-28 CAL792 HAN → TPE May 28, 04:50 UTCMay 28, 07:20 UTC2h 30m
2026-05-28 CAL791 TPE → HAN May 28, 00:55 UTCMay 28, 03:10 UTC2h 15m
2026-05-27 CAL117 FUK → TPE May 27, 13:50 UTCMay 27, 14:15 UTC25m
2026-05-27 CAL116 TPE → FUK May 27, 09:05 UTCMay 27, 09:35 UTC30m
2026-05-27 CAL157 KIX → TPE May 27, 06:44 UTCMay 27, 07:10 UTC25m
2026-05-27 CAL157 KIX → TPE May 27, 04:55 UTCMay 27, 05:29 UTC35m
2026-05-27 CAL156 TPE → KIX May 27, 00:44 UTCMay 27, 02:59 UTC2h 15m
2026-05-26 CAL920 HKG → TPE May 26, 12:54 UTCMay 26, 14:20 UTC1h 25m
2026-05-26 CAL919 TPE → HKG May 26, 10:29 UTCMay 26, 10:44 UTC15m
2026-05-26 CAL919 TPE → HKG May 26, 09:29 UTCMay 26, 09:55 UTC25m
2026-05-26 CAL834 BKK → TPE May 26, 04:10 UTCMay 26, 07:29 UTC3h 20m
2026-05-25 CAL833 TPE → BKK May 25, 23:19 UTCMay 26, 02:35 UTC3h 15m
2026-05-25 CAL163 ICN → TPE May 25, 11:35 UTCMay 25, 13:40 UTC2h 5m
2026-05-25 CAL162 TPE → ICN May 25, 07:45 UTCMay 25, 09:50 UTC2h 5m
2026-05-25 CAL161 ICN → TPE May 25, 03:55 UTCMay 25, 05:55 UTC2h 0m
2026-05-25 CAL160 TPE → ICN May 25, 01:55 UTCMay 25, 02:15 UTC20m
2026-05-24 CAL163 ICN → TPE May 24, 11:35 UTCMay 24, 13:55 UTC2h 20m
2026-05-24 CAL162 TPE → ICN May 24, 07:45 UTCMay 24, 09:55 UTC2h 10m
2026-05-24 CAL161 ICN → TPE May 24, 05:40 UTCMay 24, 05:55 UTC15m
2026-05-24 CAL161 ICN → TPE May 24, 03:55 UTCMay 24, 04:25 UTC30m
2026-05-24 CAL160 TPE → ICN May 24, 00:10 UTCMay 24, 02:15 UTC2h 5m
2026-05-23 CAL111 FUK → TPE May 23, 04:25 UTCMay 23, 04:55 UTC30m
2026-05-23 CAL111 FUK → TPE May 23, 02:55 UTCMay 23, 03:05 UTC10m
2026-05-22 CAL110 TPE → FUK May 22, 23:10 UTCMay 22, 23:35 UTC25m
2026-05-22 CAL528 SZX → TPE May 22, 11:40 UTCMay 22, 12:05 UTC25m
2026-05-22 CAL528 SZX → TPE May 22, 10:45 UTCMay 22, 10:55 UTC10m
2026-05-22 CAL527 TPE → SZX May 22, 07:15 UTCMay 22, 07:45 UTC30m
2026-05-22 MDA992 TPE → TPE May 22, 01:00 UTCMay 22, 05:00 UTC4h 0m
2026-05-21 CAL163 ICN → TPE May 21, 13:30 UTCMay 21, 14:00 UTC30m
2026-05-21 CAL163 ICN → TPE May 21, 11:50 UTCMay 21, 12:15 UTC25m
2026-05-21 CAL162 TPE → ICN May 21, 08:05 UTCMay 21, 10:05 UTC2h 0m
2026-05-21 CAL161 ICN → TPE May 21, 06:10 UTCMay 21, 06:35 UTC25m
2026-05-21 CAL161 ICN → TPE May 21, 04:25 UTCMay 21, 04:45 UTC20m
2026-05-21 CAL160 TPE → ICN May 21, 00:15 UTCMay 21, 02:20 UTC2h 5m
2026-05-20 CAL163 ICN → TPE May 20, 13:40 UTCMay 20, 14:05 UTC25m
2026-05-20 CAL163 ICN → TPE May 20, 11:55 UTCMay 20, 12:20 UTC25m
2026-05-20 CAL162 TPE → ICN May 20, 09:25 UTCMay 20, 10:00 UTC35m
2026-05-20 CAL162 TPE → ICN May 20, 07:50 UTCMay 20, 08:10 UTC20m
2026-05-20 CAL161 ICN → TPE May 20, 05:55 UTCMay 20, 06:15 UTC20m
2026-05-20 CAL161 ICN → TPE May 20, 04:10 UTCMay 20, 04:35 UTC25m
2026-05-20 CAL160 TPE → ICN May 20, 00:25 UTCMay 20, 02:30 UTC2h 5m
2026-05-19 CAL163 ICN → TPE May 19, 13:20 UTCMay 19, 13:40 UTC20m
2026-05-19 CAL163 ICN → TPE May 19, 11:40 UTCMay 19, 12:05 UTC25m
2026-05-19 CAL162 TPE → ICN May 19, 07:55 UTCMay 19, 09:55 UTC2h 0m

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-18307 page for operator, model, and routing details .

Mode-S 8991B5 frequently asked

What is Mode-S code 8991B5?
8991B5 is an ICAO 24-bit transponder address. Allocated to Taiwan. Assigned to B-18307.
Where is Mode-S 8991B5 registered?
Mode-S code 8991B5 is allocated to Taiwan (TW). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8991B5 broadcasting right now?
Yes. Mode-S 8991B5 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8991B5, octal 42310665, decimal 9,015,733.
What flights does 8991B5 operate?
Mode-S 8991B5 has broadcast 20 distinct callsigns, including CAL161, CAL117, CAL163, CAL116, CAL835.