sensors Mode-S transponder

8990A4

ICAO 24-bit transponder address · allocated to Taiwan

Currently assigned to B-18772 · BOEING 777-200LR

Hex
8990A4
Octal
42310244
Decimal
9,015,460
Country
TW
Tail
B-18772
Type
B77L
No current signal · last broadcast 3h ago
Flights observed
150
Distinct callsigns
20
Country
TW
Last broadcast
3h ago

Last known position

Most recent position reported by Mode-S 8990A4.

Country allocation

The ICAO 24-bit address 8990A4 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
CAL5381 China Airlines 22 2026-05-25
CAL5382 China Airlines 19 2026-05-24
CAL5522 China Airlines 9 2026-05-19
CAL5309 China Airlines 9 2026-04-20
CAL5312 China Airlines 8 2026-05-27
CAL5311 China Airlines 8 2026-05-28
CAL5346 China Airlines 7 2026-05-22
CAL5345 China Airlines 7 2026-05-23
CAL5142 China Airlines 7 2026-05-17
CAL5141 China Airlines 7 2026-05-18
CAL5021 China Airlines 6 2026-05-18
CAL5116 China Airlines 4 2026-05-28
CAL5313 China Airlines 3 2026-05-08
CAL5310 China Airlines 3 2026-04-19
CAL5225 China Airlines 3 2026-05-13
CAL5165 China Airlines 3 2026-05-10
CAL5122 China Airlines 3 2026-05-07
CAL6658 - 2 2026-05-26
CAL6657 - 2 2026-05-25
CAL5884 China Airlines 2 2026-04-29

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 CAL5166 TPE → LAX May 29, 20:10 UTCMay 29, 22:35 UTC2h 25m
2026-05-29 CAL5115 LAX → TPE May 29, 00:35 UTCMay 29, 14:20 UTC13h 45m
2026-05-28 CAL5116 TPE → LAX May 28, 12:00 UTCMay 28, 21:45 UTC9h 45m
2026-05-28 CAL5116 TPE → LAX May 28, 10:10 UTCMay 28, 10:25 UTC15m
2026-05-28 CAL5311 JFK → ANC May 28, 06:50 UTCMay 28, 07:25 UTC35m
2026-05-27 CAL5311 JFK → ANC May 27, 21:45 UTCMay 28, 05:30 UTC7h 45m
2026-05-27 CAL5311 JFK → ANC May 27, 13:00 UTCMay 27, 20:05 UTC7h 5m
2026-05-27 CAL5312 ANC → JFK May 27, 03:39 UTCMay 27, 09:50 UTC6h 10m
2026-05-26 CAL5312 ANC → JFK May 26, 17:30 UTCMay 27, 02:09 UTC8h 40m
2026-05-26 CAL6658 - May 26, 05:05 UTCMay 26, 08:59 UTC3h 55m
2026-05-25 CAL6657 - May 25, 23:00 UTCMay 26, 02:49 UTC3h 50m
2026-05-25 CAL5381 MIA → TPE May 25, 07:35 UTCMay 25, 19:20 UTC11h 45m
2026-05-25 CAL5381 MIA → TPE May 25, 01:55 UTCMay 25, 05:40 UTC3h 45m
2026-05-24 CAL5382 TPE → MIA May 24, 17:25 UTCMay 24, 21:45 UTC4h 20m
2026-05-24 CAL5382 TPE → MIA May 24, 05:30 UTCMay 24, 15:45 UTC10h 15m
2026-05-24 CAL5382 TPE → MIA May 24, 04:00 UTCMay 24, 04:15 UTC15m
2026-05-23 CAL5345 SFO → TPE May 23, 11:30 UTCMay 24, 00:45 UTC13h 16m
2026-05-23 CAL5345 SFO → TPE May 23, 04:00 UTCMay 23, 08:25 UTC4h 25m
2026-05-22 CAL5346 SFO → ATL May 22, 21:30 UTCMay 23, 01:40 UTC4h 10m
2026-05-22 CAL5346 SFO → ATL May 22, 07:50 UTCMay 22, 18:40 UTC10h 50m
2026-05-21 CAL5161 LAX → TPE May 21, 11:05 UTCMay 21, 11:35 UTC30m
2026-05-20 CAL5161 LAX → TPE May 20, 21:55 UTCMay 20, 22:50 UTC55m
2026-05-20 CAL5162 TPE → LAX May 20, 09:30 UTCMay 20, 19:05 UTC9h 35m
2026-05-20 CAL5162 TPE → LAX May 20, 07:40 UTCMay 20, 08:00 UTC20m
2026-05-19 CAL5522 FRA → TPE May 19, 12:25 UTCMay 20, 02:30 UTC14h 5m
2026-05-18 CAL5021 TPE → DWC May 18, 18:15 UTCMay 19, 09:05 UTC14h 49m
2026-05-18 CAL5141 MIA → IAH May 18, 13:00 UTCMay 18, 13:25 UTC25m
2026-05-18 CAL5141 MIA → IAH May 18, 11:15 UTCMay 18, 11:45 UTC30m
2026-05-17 CAL5141 MIA → IAH May 17, 19:35 UTCMay 18, 08:25 UTC12h 50m
2026-05-17 CAL5142 TPE → ANC May 17, 05:00 UTCMay 17, 16:30 UTC11h 30m
2026-05-17 CAL5142 TPE → ANC May 17, 02:20 UTCMay 17, 03:00 UTC40m
2026-05-17 CAL5142 TPE → ANC May 17, 00:45 UTCMay 17, 00:55 UTC10m
2026-05-16 CAL5381 MIA → TPE May 16, 19:15 UTCMay 16, 19:40 UTC25m
2026-05-16 CAL5381 MIA → TPE May 16, 07:31 UTCMay 16, 17:55 UTC10h 25m
2026-05-15 CAL5381 MIA → TPE May 15, 23:15 UTCMay 16, 05:10 UTC5h 55m
2026-05-15 CAL5382 TPE → MIA May 15, 16:25 UTCMay 15, 20:40 UTC4h 15m
2026-05-15 CAL5382 TPE → MIA May 15, 03:25 UTCMay 15, 14:20 UTC10h 55m
2026-05-14 CAL5345 SFO → TPE May 14, 22:35 UTCMay 14, 23:00 UTC25m
2026-05-14 CAL5345 SFO → TPE May 14, 10:35 UTCMay 14, 21:15 UTC10h 40m
2026-05-14 CAL5345 SFO → TPE May 14, 02:30 UTCMay 14, 07:00 UTC4h 30m
2026-05-13 CAL5346 SFO → ATL May 13, 20:20 UTCMay 14, 00:20 UTC4h 0m
2026-05-13 CAL5346 SFO → ATL May 13, 07:35 UTCMay 13, 18:20 UTC10h 45m
2026-05-13 CAL5225 ORD → ANC May 13, 04:25 UTCMay 13, 05:00 UTC35m
2026-05-12 CAL5225 ORD → ANC May 12, 19:20 UTCMay 13, 02:55 UTC7h 35m
2026-05-12 CAL5225 ORD → ANC May 12, 11:50 UTCMay 12, 17:50 UTC6h 0m
2026-05-12 CAL5226 ANC → ORD May 12, 04:00 UTCMay 12, 09:05 UTC5h 5m
2026-05-11 CAL5226 ANC → ORD May 11, 17:55 UTCMay 11, 20:30 UTC2h 35m
2026-05-11 CAL5115 LAX → TPE May 11, 00:49 UTCMay 11, 14:25 UTC13h 35m
2026-05-10 CAL5116 TPE → LAX May 10, 12:19 UTCMay 10, 21:49 UTC9h 30m
2026-05-10 CAL5116 TPE → LAX May 10, 10:40 UTCMay 10, 10:49 UTC10m

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-18772 page for operator, model, and routing details .

Mode-S 8990A4 frequently asked

What is Mode-S code 8990A4?
8990A4 is an ICAO 24-bit transponder address. Allocated to Taiwan. Assigned to B-18772.
Where is Mode-S 8990A4 registered?
Mode-S code 8990A4 is allocated to Taiwan (TW). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8990A4 broadcasting right now?
No active broadcast right now. Last signal was 3h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8990A4, octal 42310244, decimal 9,015,460.
What flights does 8990A4 operate?
Mode-S 8990A4 has broadcast 20 distinct callsigns, including CAL5381, CAL5382, CAL5522, CAL5309, CAL5312.