Apparatus

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sensors Mode-S transponder

8991D4

ICAO 24-bit transponder address · allocated to Taiwan

Currently assigned to B-58206 · AIRBUS A-321neo

Hex
8991D4
Octal
42310724
Decimal
9,015,764
Country
TW
Tail
B-58206
Type
A21N
No current signal · last broadcast Jul 26, 14:50 UTC
Flights observed
334
Distinct callsigns
20
Country
TW
Last broadcast
Jul 26, 14:50 UTC

Last known position

Most recent position reported by Mode-S 8991D4.

Country allocation

The ICAO 24-bit address 8991D4 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
SJX786 - 18 2026-07-08
SJX785 STARLUX Airlines 18 2026-07-07
SJX714 - 12 2026-07-08
SJX761 STARLUX Airlines 11 2026-06-27
SJX331 STARLUX Airlines 11 2026-05-28
SJX902 STARLUX Airlines 10 2026-07-24
SJX900 STARLUX Airlines 10 2026-07-26
SJX792 STARLUX Airlines 10 2026-07-26
SJX307 STARLUX Airlines 10 2026-05-26
SJX301 STARLUX Airlines 10 2026-05-28
SJX791 STARLUX Airlines 9 2026-07-26
SJX306 STARLUX Airlines 9 2026-05-26
SJX903 STARLUX Airlines 8 2026-07-24
SJX835 STARLUX Airlines 7 2026-07-21
SJX713 - 7 2026-06-18
SJX332 STARLUX Airlines 7 2026-05-27
SJX313 STARLUX Airlines 7 2026-05-26
SJX300 STARLUX Airlines 7 2026-05-28
SJX901 STARLUX Airlines 6 2026-07-26
SJX834 STARLUX Airlines 6 2026-07-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 SJX792 CRK → TPE Jul 26, 13:10 UTCJul 26, 14:50 UTC1h 40m
2026-07-26 SJX791 TPE → CRK Jul 26, 09:35 UTCJul 26, 11:10 UTC1h 35m
2026-07-26 SJX901 PUS → TPE Jul 26, 06:20 UTCJul 26, 08:15 UTC1h 56m
2026-07-26 SJX900 TPE → PUS Jul 26, 04:15 UTCJul 26, 04:40 UTC25m
2026-07-26 SJX900 TPE → PUS Jul 26, 02:50 UTCJul 26, 03:20 UTC30m
2026-07-25 SJX204 MFM → TPE Jul 25, 12:25 UTCJul 25, 14:00 UTC1h 35m
2026-07-25 SJX203 TPE → MFM Jul 25, 08:05 UTCJul 25, 09:55 UTC1h 50m
2026-07-25 SJX891 - Jul 25, 05:45 UTCJul 25, 06:15 UTC30m
2026-07-25 SJX890 TPE → SHI Jul 25, 03:10 UTCJul 25, 03:35 UTC25m
2026-07-25 SJX2524 - Jul 25, 00:25 UTCJul 25, 00:55 UTC30m
2026-07-24 SJX903 PUS → TPE Jul 24, 11:55 UTCJul 24, 12:55 UTC1h 0m
2026-07-24 SJX903 PUS → TPE Jul 24, 10:25 UTCJul 24, 10:45 UTC20m
2026-07-24 SJX902 TPE → PUS Jul 24, 08:30 UTCJul 24, 08:50 UTC20m
2026-07-24 SJX902 TPE → PUS Jul 24, 07:00 UTCJul 24, 07:25 UTC25m
2026-07-23 SJX903 PUS → TPE Jul 23, 10:30 UTCJul 23, 12:20 UTC1h 50m
2026-07-23 SJX902 - Jul 23, 08:45 UTCJul 23, 09:05 UTC20m
2026-07-23 SJX902 - Jul 23, 07:15 UTCJul 23, 07:35 UTC20m
2026-07-22 SJX792 CRK → TPE Jul 22, 12:45 UTCJul 22, 14:25 UTC1h 40m
2026-07-22 SJX1900 TPE → PUS Jul 22, 02:55 UTCJul 22, 04:45 UTC1h 50m
2026-07-21 SJX903 PUS → TPE Jul 21, 11:50 UTCJul 21, 12:15 UTC25m
2026-07-21 SJX903 PUS → TPE Jul 21, 10:20 UTCJul 21, 10:40 UTC20m
2026-07-21 SJX902 - Jul 21, 08:35 UTCJul 21, 09:05 UTC30m
2026-07-21 SJX902 - Jul 21, 07:05 UTCJul 21, 07:35 UTC30m
2026-07-21 SJX835 UKB → TPE Jul 21, 05:00 UTCJul 21, 05:15 UTC15m
2026-07-21 SJX835 UKB → TPE Jul 21, 03:00 UTCJul 21, 03:45 UTC45m
2026-07-20 SJX834 TPE → UKB Jul 20, 23:05 UTCJul 21, 01:25 UTC2h 19m
2026-07-20 SJX703 TPE → TPE Jul 20, 07:50 UTCJul 20, 14:15 UTC6h 25m
2026-07-19 SJX781 TPE → TPE Jul 19, 23:15 UTCJul 20, 05:30 UTC6h 15m
2026-07-19 SJX2500 - Jul 19, 18:00 UTCJul 19, 18:30 UTC30m
2026-07-19 SJX2500 TPE → TPE Jul 19, 17:15 UTCJul 19, 17:35 UTC20m
2026-07-19 SJX784 CEB → TPE Jul 19, 08:25 UTCJul 19, 14:55 UTC6h 30m
2026-07-19 SJX835 UKB → TPE Jul 19, 03:00 UTCJul 19, 05:20 UTC2h 20m
2026-07-18 SJX834 TPE → UKB Jul 18, 23:05 UTCJul 19, 01:25 UTC2h 20m
2026-07-18 SJX752 - Jul 18, 10:20 UTCJul 18, 13:50 UTC3h 30m
2026-07-18 SJX751 - Jul 18, 05:45 UTCJul 18, 09:00 UTC3h 15m
2026-07-18 SJX790 CRK → TPE Jul 18, 02:29 UTCJul 18, 04:10 UTC1h 41m
2026-07-17 SJX789 - Jul 17, 23:20 UTCJul 18, 01:00 UTC1h 40m
2026-07-17 SJX752 - Jul 17, 10:55 UTCJul 17, 14:20 UTC3h 25m
2026-07-17 SJX751 - Jul 17, 05:39 UTCJul 17, 08:59 UTC3h 20m
2026-07-17 SJX790 CRK → TPE Jul 17, 02:15 UTCJul 17, 03:55 UTC1h 40m
2026-07-16 SJX789 - Jul 16, 23:05 UTCJul 17, 00:45 UTC1h 40m
2026-07-16 SJX792 - Jul 16, 12:30 UTCJul 16, 14:25 UTC1h 55m
2026-07-16 SJX791 - Jul 16, 09:35 UTCJul 16, 11:10 UTC1h 35m
2026-07-16 SJX901 - Jul 16, 07:40 UTCJul 16, 08:00 UTC20m
2026-07-16 SJX901 - Jul 16, 06:10 UTCJul 16, 06:30 UTC20m
2026-07-16 SJX900 - Jul 16, 04:35 UTCJul 16, 04:55 UTC20m
2026-07-16 SJX900 - Jul 16, 03:00 UTCJul 16, 03:15 UTC15m
2026-07-15 SJX726 - Jul 15, 09:30 UTCJul 15, 14:10 UTC4h 40m
2026-07-15 SJX725 - Jul 15, 03:40 UTCJul 15, 07:50 UTC4h 10m
2026-07-14 SJX704 - Jul 14, 07:55 UTCJul 14, 14:30 UTC6h 35m

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-58206 page for operator, model, and routing details .

Mode-S 8991D4 frequently asked

What is Mode-S code 8991D4?
8991D4 is an ICAO 24-bit transponder address. Allocated to Taiwan. Assigned to B-58206.
Where is Mode-S 8991D4 registered?
Mode-S code 8991D4 is allocated to Taiwan (TW). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8991D4 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 14:50 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8991D4, octal 42310724, decimal 9,015,764.
What flights does 8991D4 operate?
Mode-S 8991D4 has broadcast 20 distinct callsigns, including SJX786, SJX785, SJX714, SJX761, SJX331.