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sensors Mode-S transponder

8990A2

ICAO 24-bit transponder address · allocated to Taiwan

Currently assigned to B-18653 · BOEING 737-800

Hex
8990A2
Octal
42310242
Decimal
9,015,458
Country
TW
Tail
B-18653
Type
B738
Broadcasting now · callsign CAL712 · 1,600 ft
Flights observed
391
Distinct callsigns
20
Country
TW
Last broadcast
56m ago

Current position

8990A2 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 8990A2 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
CAL839 - 58 2026-07-13
CAL840 - 57 2026-07-13
CAL757 - 53 2026-07-11
MDA983 - 45 2026-07-12
CAL758 - 41 2026-07-11
CAL712 - 41 2026-07-14
CAL711 - 40 2026-07-13
MDA984 - 38 2026-07-13
MDA303 Mandarin Airlines 3 2026-06-12
MDA354 Mandarin Airlines 2 2026-06-12
MDA353 Mandarin Airlines 2 2026-06-12
MDA352 Mandarin Airlines 1 2026-06-12
MDA351 Mandarin Airlines 1 2026-06-12
MDA346 Mandarin Airlines 1 2026-05-10
MDA345 Mandarin Airlines 1 2026-05-10
MDA332 Mandarin Airlines 1 2026-05-15
MDA331 Mandarin Airlines 1 2026-05-14
MDA308 Mandarin Airlines 1 2026-05-10
MDA307 Mandarin Airlines 1 2026-05-10
MDA304 Mandarin Airlines 1 2026-06-12

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 CAL712 - Jul 14, 02:15 UTCJul 14, 02:30 UTC15m
2026-07-13 CAL711 KHH → MNL Jul 13, 23:35 UTCJul 14, 00:55 UTC1h 20m
2026-07-13 CAL840 - Jul 13, 11:30 UTCJul 13, 14:40 UTC3h 10m
2026-07-13 CAL839 - Jul 13, 09:25 UTCJul 13, 09:50 UTC25m
2026-07-13 CAL839 - Jul 13, 06:45 UTCJul 13, 07:10 UTC25m
2026-07-13 MDA984 HKG → KHH Jul 13, 02:45 UTCJul 13, 03:50 UTC1h 5m
2026-07-12 MDA983 KHH → HKG Jul 12, 23:45 UTCJul 13, 00:55 UTC1h 10m
2026-07-12 CAL840 - Jul 12, 14:15 UTCJul 12, 14:45 UTC30m
2026-07-12 CAL840 - Jul 12, 11:40 UTCJul 12, 11:55 UTC15m
2026-07-12 CAL839 - Jul 12, 09:35 UTCJul 12, 09:50 UTC15m
2026-07-12 CAL839 - Jul 12, 06:50 UTCJul 12, 07:20 UTC30m
2026-07-12 CAL712 - Jul 12, 02:55 UTCJul 12, 04:15 UTC1h 20m
2026-07-12 CAL711 - Jul 12, 00:05 UTCJul 12, 01:35 UTC1h 30m
2026-07-11 CAL758 - Jul 11, 22:05 UTCJul 11, 22:35 UTC30m
2026-07-11 CAL758 - Jul 11, 18:30 UTCJul 11, 18:45 UTC15m
2026-07-11 CAL757 - Jul 11, 15:25 UTCJul 11, 15:55 UTC30m
2026-07-11 CAL757 - Jul 11, 12:05 UTCJul 11, 12:15 UTC10m
2026-07-11 CAL840 - Jul 11, 08:10 UTCJul 11, 08:25 UTC15m
2026-07-11 CAL840 - Jul 11, 05:25 UTCJul 11, 05:40 UTC15m
2026-07-10 CAL839 KHH → BKK Jul 10, 06:50 UTCJul 10, 09:55 UTC3h 5m
2026-07-10 CAL712 - Jul 10, 02:30 UTCJul 10, 04:00 UTC1h 30m
2026-07-09 CAL711 KHH → MNL Jul 9, 23:35 UTCJul 10, 00:55 UTC1h 20m
2026-07-09 CAL758 - Jul 9, 14:20 UTCJul 9, 14:50 UTC30m
2026-07-09 CAL757 - Jul 9, 08:25 UTCJul 9, 09:05 UTC40m
2026-07-09 CAL757 - Jul 9, 05:15 UTCJul 9, 05:35 UTC20m
2026-07-09 MDA984 HKG → KHH Jul 9, 02:20 UTCJul 9, 03:25 UTC1h 5m
2026-07-08 MDA983 KHH → HKG Jul 8, 23:35 UTCJul 9, 00:35 UTC1h 0m
2026-07-08 CAL840 - Jul 8, 11:30 UTCJul 8, 14:35 UTC3h 5m
2026-07-08 CAL839 KHH → BKK Jul 8, 06:45 UTCJul 8, 09:50 UTC3h 5m
2026-07-08 CAL712 - Jul 8, 02:10 UTCJul 8, 03:30 UTC1h 20m
2026-07-07 CAL711 KHH → MNL Jul 7, 23:40 UTCJul 8, 01:00 UTC1h 20m
2026-07-07 CAL758 - Jul 7, 10:30 UTCJul 7, 14:35 UTC4h 5m
2026-07-07 CAL757 - Jul 7, 05:05 UTCJul 7, 08:50 UTC3h 45m
2026-07-06 CAL840 - Jul 6, 11:45 UTCJul 6, 14:50 UTC3h 5m
2026-07-06 CAL839 - Jul 6, 09:25 UTCJul 6, 10:20 UTC55m
2026-07-06 CAL839 - Jul 6, 07:20 UTCJul 6, 07:55 UTC35m
2026-07-06 MDA984 HKG → KHH Jul 6, 02:10 UTCJul 6, 03:20 UTC1h 10m
2026-07-05 MDA983 - Jul 5, 23:30 UTCJul 6, 00:35 UTC1h 5m
2026-07-05 CAL840 - Jul 5, 11:30 UTCJul 5, 14:35 UTC3h 5m
2026-07-05 CAL839 KHH → BKK Jul 5, 07:00 UTCJul 5, 10:10 UTC3h 10m
2026-07-05 CAL712 - Jul 5, 02:15 UTCJul 5, 03:40 UTC1h 25m
2026-07-04 CAL711 KHH → MNL Jul 4, 23:35 UTCJul 5, 01:05 UTC1h 30m
2026-07-04 CAL758 - Jul 4, 14:05 UTCJul 4, 14:35 UTC30m
2026-07-04 CAL757 - Jul 4, 08:35 UTCJul 4, 08:55 UTC20m
2026-07-04 CAL757 - Jul 4, 05:15 UTCJul 4, 05:55 UTC40m
2026-07-04 MDA984 HKG → KHH Jul 4, 02:40 UTCJul 4, 03:50 UTC1h 10m
2026-07-04 MDA983 - Jul 4, 00:35 UTCJul 4, 00:50 UTC15m
2026-07-03 MDA983 - Jul 3, 23:40 UTCJul 4, 00:00 UTC20m
2026-07-03 CAL840 - Jul 3, 11:50 UTCJul 3, 14:50 UTC3h 0m
2026-07-03 CAL839 KHH → BKK Jul 3, 06:45 UTCJul 3, 09:45 UTC3h 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-18653 page for operator, model, and routing details .

Mode-S 8990A2 frequently asked

What is Mode-S code 8990A2?
8990A2 is an ICAO 24-bit transponder address. Allocated to Taiwan. Assigned to B-18653.
Where is Mode-S 8990A2 registered?
Mode-S code 8990A2 is allocated to Taiwan (TW). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8990A2 broadcasting right now?
Yes. Mode-S 8990A2 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8990A2, octal 42310242, decimal 9,015,458.
What flights does 8990A2 operate?
Mode-S 8990A2 has broadcast 20 distinct callsigns, including CAL839, CAL840, CAL757, MDA983, CAL758.