Apparatus

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sensors Mode-S transponder

71C547

ICAO 24-bit transponder address · allocated to Korea, South

Currently assigned to HL8547 · BOEING 737-800

Hex
71C547
Octal
34342507
Decimal
7,456,071
Country
KR
Tail
HL8547
Type
B738
Broadcasting now · callsign TWB727 · 15,975 ft
Flights observed
419
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 16:35 UTC

Current position

71C547 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 71C547 falls within the block assigned to Korea, South (KR) by ICAO Annex 10, Volume III. Every aircraft registered in Korea, South 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
TWB669 Tway Airlines 8 2026-07-24
TWB664 Tway Airlines 8 2026-05-27
TWB643 Tway Airlines 8 2026-07-26
TWB305 Tway Airlines 8 2026-07-21
TWB322 - 7 2026-06-17
TWB314 Tway Airlines 7 2026-07-21
TWB808 - 6 2026-07-23
TWB702 Tway Airlines 6 2026-07-21
TWB676 - 6 2026-06-18
TWB663 Tway Airlines 6 2026-05-27
TWB644 Tway Airlines 6 2026-07-26
TWB321 - 6 2026-06-17
TWB312 - 6 2026-07-10
TWB252 - 6 2026-07-15
TWB216 - 6 2026-07-15
TWB208 - 6 2026-06-30
TWB801 Tway Airlines 5 2026-07-21
TWB690 - 5 2026-06-23
TWB689 - 5 2026-06-23
TWB670 Tway Airlines 5 2026-07-24

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 TWB644 HKG → ICN Jul 26, 13:25 UTCJul 26, 16:35 UTC3h 10m
2026-07-26 TWB643 ICN → HKG Jul 26, 10:55 UTCJul 26, 11:10 UTC15m
2026-07-26 TWB643 ICN → HKG Jul 26, 07:55 UTCJul 26, 10:20 UTC2h 25m
2026-07-25 TWB608 TAO → ICN Jul 25, 14:00 UTCJul 25, 14:35 UTC35m
2026-07-25 TWB607 ICN → TAO Jul 25, 11:10 UTCJul 25, 11:40 UTC30m
2026-07-25 TWB644 HKG → ICN Jul 25, 08:15 UTCJul 25, 09:00 UTC45m
2026-07-25 TWB644 HKG → ICN Jul 25, 05:50 UTCJul 25, 06:05 UTC15m
2026-07-25 TWB643 ICN → HKG Jul 25, 00:15 UTCJul 25, 03:40 UTC3h 25m
2026-07-24 TWB308 KIX → ICN Jul 24, 15:40 UTCJul 24, 17:00 UTC1h 20m
2026-07-24 TWB307 - Jul 24, 13:10 UTCJul 24, 14:25 UTC1h 15m
2026-07-24 TWB670 RMQ → ICN Jul 24, 09:10 UTCJul 24, 11:25 UTC2h 15m
2026-07-24 TWB669 ICN → RMQ Jul 24, 07:10 UTCJul 24, 07:45 UTC35m
2026-07-24 TWB669 ICN → RMQ Jul 24, 05:30 UTCJul 24, 06:00 UTC30m
2026-07-23 TWB014 DAD → ICN Jul 23, 12:45 UTCJul 23, 23:45 UTC11h 0m
2026-07-23 TWB808 - Jul 23, 10:10 UTCJul 23, 10:30 UTC20m
2026-07-23 TWB907 - Jul 23, 08:10 UTCJul 23, 08:20 UTC10m
2026-07-23 TWB906 - Jul 23, 07:00 UTCJul 23, 07:15 UTC15m
2026-07-23 TWB332 KIX → CJU Jul 23, 03:25 UTCJul 23, 04:20 UTC55m
2026-07-23 TWB319 PUS → KIX Jul 23, 00:50 UTCJul 23, 01:50 UTC1h 0m
2026-07-22 TWB640 HKG → PUS Jul 22, 18:25 UTCJul 22, 21:30 UTC3h 5m
2026-07-22 TWB639 PUS → HKG Jul 22, 13:10 UTCJul 22, 16:15 UTC3h 5m
2026-07-22 TWB320 KIX → PUS Jul 22, 11:25 UTCJul 22, 11:35 UTC10m
2026-07-21 TWB702 CJU → GMP Jul 21, 23:45 UTCJul 22, 00:30 UTC45m
2026-07-21 TWB801 TAE → CJU Jul 21, 21:50 UTCJul 21, 22:05 UTC15m
2026-07-21 TWB314 KIX → TAE Jul 21, 11:30 UTCJul 21, 12:40 UTC1h 10m
2026-07-21 TWB305 ICN → KIX Jul 21, 08:35 UTCJul 21, 10:05 UTC1h 30m
2026-07-21 TWB242 NRT → ICN Jul 21, 04:40 UTCJul 21, 06:40 UTC2h 0m
2026-07-20 TWB241 ICN → NRT Jul 20, 23:55 UTCJul 21, 01:50 UTC1h 55m
2026-07-20 TWB306 KIX → ICN Jul 20, 11:05 UTCJul 20, 12:30 UTC1h 25m
2026-07-20 TWB313 TAE → KIX Jul 20, 08:40 UTCJul 20, 09:35 UTC55m
2026-07-20 TWB214 FUK → TAE Jul 20, 06:40 UTCJul 20, 07:05 UTC25m
2026-07-20 TWB227 CJU → FUK Jul 20, 04:20 UTCJul 20, 04:50 UTC30m
2026-07-20 TWB707 GMP → CJU Jul 20, 01:35 UTCJul 20, 02:15 UTC40m
2026-07-19 TWB702 CJU → GMP Jul 19, 23:15 UTCJul 19, 23:50 UTC35m
2026-07-19 TWB801 TAE → CJU Jul 19, 21:30 UTCJul 19, 21:45 UTC15m
2026-07-19 TWB314 KIX → TAE Jul 19, 11:05 UTCJul 19, 11:35 UTC30m
2026-07-19 TWB305 ICN → KIX Jul 19, 07:10 UTCJul 19, 08:40 UTC1h 30m
2026-07-19 TWB302 KIX → ICN Jul 19, 03:05 UTCJul 19, 04:25 UTC1h 20m
2026-07-18 TWB301 ICN → KIX Jul 18, 23:25 UTCJul 19, 00:50 UTC1h 25m
2026-07-18 TWB670 RMQ → ICN Jul 18, 09:25 UTCJul 18, 11:40 UTC2h 15m
2026-07-18 TWB669 - Jul 18, 07:30 UTCJul 18, 07:50 UTC20m
2026-07-18 TWB669 - Jul 18, 05:45 UTCJul 18, 06:25 UTC40m
2026-07-17 TWB014 - Jul 17, 12:35 UTCJul 17, 23:50 UTC11h 15m
2026-07-17 TWB808 - Jul 17, 10:00 UTCJul 17, 10:30 UTC30m
2026-07-17 TWB907 - Jul 17, 07:55 UTCJul 17, 08:04 UTC10m
2026-07-17 TWB906 - Jul 17, 06:40 UTCJul 17, 06:54 UTC15m
2026-07-17 TWB715 - Jul 17, 04:25 UTCJul 17, 04:59 UTC35m
2026-07-17 TWB710 - Jul 17, 02:05 UTCJul 17, 02:39 UTC35m
2026-07-17 TWB805 - Jul 17, 00:04 UTCJul 17, 00:20 UTC15m
2026-07-16 TWB038 - Jul 16, 11:05 UTCJul 16, 21:25 UTC10h 20m

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 HL8547 page for operator, model, and routing details .

Mode-S 71C547 frequently asked

What is Mode-S code 71C547?
71C547 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8547.
Where is Mode-S 71C547 registered?
Mode-S code 71C547 is allocated to Korea, South (KR). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 71C547 broadcasting right now?
Yes. Mode-S 71C547 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C547, octal 34342507, decimal 7,456,071.
What flights does 71C547 operate?
Mode-S 71C547 has broadcast 20 distinct callsigns, including TWB669, TWB664, TWB643, TWB305, TWB322.