Apparatus

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sensors Mode-S transponder

71C531

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

Currently assigned to HL8531 · AIRBUS A-321neo

Hex
71C531
Octal
34342461
Decimal
7,456,049
Country
KR
Tail
HL8531
Type
A21N
No current signal · last broadcast Jul 26, 20:50 UTC
Flights observed
368
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 20:50 UTC

Last known position

Most recent position reported by Mode-S 71C531.

Country allocation

The ICAO 24-bit address 71C531 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
KAL656 Korean Air 10 2026-07-26
KAL2174 - 10 2026-07-09
KAL2171 - 10 2026-07-09
KAL655 Korean Air 9 2026-07-26
KAL2173 - 9 2026-07-09
KAL2172 - 9 2026-07-09
KAL2066 - 9 2026-06-26
KAL2016 - 8 2026-07-16
KAL726 - 7 2026-07-11
KAL725 - 7 2026-07-11
KAL712 Korean Air 7 2026-07-26
KAL711 Korean Air 7 2026-07-26
KAL626 Korean Air 7 2026-06-11
KAL625 Korean Air 7 2026-06-11
KAL2190 - 7 2026-07-11
KAL2130 Korean Air 7 2026-07-22
KAL2129 Korean Air 7 2026-07-22
KAL2086 Korean Air 7 2026-07-23
KAL1410 Korean Air 7 2026-07-23
KAL851 - 6 2026-06-25

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 KAL656 BKK → ICN Jul 26, 20:20 UTCJul 26, 20:50 UTC30m
2026-07-26 KAL655 ICN → BKK Jul 26, 12:40 UTCJul 26, 17:45 UTC5h 5m
2026-07-26 KAL712 NRT → ICN Jul 26, 08:45 UTCJul 26, 10:45 UTC2h 0m
2026-07-26 KAL711 ICN → NRT Jul 26, 04:35 UTCJul 26, 06:40 UTC2h 6m
2026-07-26 KAL1408 PUS → ICN Jul 26, 01:50 UTCJul 26, 02:30 UTC40m
2026-07-25 KAL1403 ICN → PUS Jul 25, 23:45 UTCJul 26, 00:30 UTC45m
2026-07-25 KAL163 ICN → DYG Jul 25, 10:50 UTCJul 25, 18:45 UTC7h 55m
2026-07-25 KAL792 OIT → ICN Jul 25, 06:15 UTCJul 25, 07:15 UTC1h 0m
2026-07-25 KAL791 ICN → FUK Jul 25, 02:25 UTCJul 25, 03:30 UTC1h 5m
2026-07-24 KAL458 DAD → ICN Jul 24, 13:10 UTCJul 24, 13:25 UTC15m
2026-07-24 KAL457 ICN → DAD Jul 24, 03:05 UTCJul 24, 10:05 UTC7h 0m
2026-07-23 KAL689 ICN → PNH Jul 23, 10:40 UTCJul 23, 22:40 UTC12h 0m
2026-07-23 KAL1410 PUS → ICN Jul 23, 07:40 UTCJul 23, 08:35 UTC55m
2026-07-23 KAL2086 TPE → PUS Jul 23, 04:15 UTCJul 23, 06:05 UTC1h 50m
2026-07-23 KAL2085 PUS → TPE Jul 23, 00:40 UTCJul 23, 02:30 UTC1h 50m
2026-07-22 KAL2130 NRT → PUS Jul 22, 04:00 UTCJul 22, 12:20 UTC8h 20m
2026-07-22 KAL2129 PUS → NRT Jul 22, 00:35 UTCJul 22, 02:10 UTC1h 35m
2026-07-21 KAL2132 NRT → PUS Jul 21, 10:35 UTCJul 21, 12:25 UTC1h 50m
2026-07-21 KAL2131 PUS → NRT Jul 21, 07:15 UTCJul 21, 08:55 UTC1h 40m
2026-07-21 KAL2130 NRT → PUS Jul 21, 04:00 UTCJul 21, 05:40 UTC1h 40m
2026-07-21 KAL2129 PUS → NRT Jul 21, 00:50 UTCJul 21, 02:20 UTC1h 30m
2026-07-20 KAL1401 ICN → PUS Jul 20, 21:55 UTCJul 20, 22:35 UTC40m
2026-07-20 KAL161 ICN → KMG Jul 20, 10:05 UTCJul 20, 19:10 UTC9h 5m
2026-07-19 KAL485 ICN → ICN Jul 19, 10:30 UTCJul 19, 23:00 UTC12h 30m
2026-07-19 KAL856 - Jul 19, 06:55 UTCJul 19, 07:20 UTC25m
2026-07-19 KAL855 - Jul 19, 01:55 UTCJul 19, 02:25 UTC30m
2026-07-18 KAL772 CTS → PUS Jul 18, 12:15 UTCJul 18, 14:35 UTC2h 20m
2026-07-18 KAL771 - Jul 18, 08:20 UTCJul 18, 10:35 UTC2h 15m
2026-07-18 KAL656 - Jul 18, 00:39 UTCJul 18, 01:15 UTC35m
2026-07-17 KAL656 - Jul 17, 22:20 UTCJul 17, 23:25 UTC1h 5m
2026-07-17 KAL656 - Jul 17, 20:04 UTCJul 17, 20:20 UTC15m
2026-07-17 KAL655 - Jul 17, 17:30 UTCJul 17, 17:40 UTC10m
2026-07-17 KAL655 - Jul 17, 12:40 UTCJul 17, 15:29 UTC2h 50m
2026-07-17 KAL712 - Jul 17, 08:54 UTCJul 17, 10:50 UTC1h 55m
2026-07-17 KAL711 ICN → NRT Jul 17, 04:20 UTCJul 17, 06:20 UTC2h 0m
2026-07-16 KAL2016 - Jul 16, 09:05 UTCJul 16, 09:45 UTC40m
2026-07-16 KAL2016 - Jul 16, 06:30 UTCJul 16, 07:55 UTC1h 25m
2026-07-16 KAL2015 - Jul 16, 01:30 UTCJul 16, 04:30 UTC3h 0m
2026-07-15 KAL485 ICN → ICN Jul 15, 10:30 UTCJul 15, 22:45 UTC12h 15m
2026-07-15 KAL1410 PUS → ICN Jul 15, 07:45 UTCJul 15, 08:30 UTC45m
2026-07-15 KAL2086 - Jul 15, 05:50 UTCJul 15, 06:30 UTC40m
2026-07-15 KAL2086 - Jul 15, 04:20 UTCJul 15, 04:40 UTC20m
2026-07-15 KAL2085 - Jul 15, 01:55 UTCJul 15, 02:10 UTC15m
2026-07-15 KAL2085 - Jul 15, 00:25 UTCJul 15, 00:45 UTC20m
2026-07-14 KAL2132 - Jul 14, 10:25 UTCJul 14, 12:00 UTC1h 35m
2026-07-14 KAL2131 PUS → NRT Jul 14, 07:05 UTCJul 14, 08:45 UTC1h 40m
2026-07-14 KAL2130 - Jul 14, 03:50 UTCJul 14, 05:30 UTC1h 40m
2026-07-14 KAL2129 PUS → NRT Jul 14, 00:40 UTCJul 14, 02:20 UTC1h 40m
2026-07-13 KAL2132 NRT → PUS Jul 13, 10:35 UTCJul 13, 12:10 UTC1h 35m
2026-07-13 KAL2131 - Jul 13, 07:05 UTCJul 13, 09:00 UTC1h 55m

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 HL8531 page for operator, model, and routing details .

Mode-S 71C531 frequently asked

What is Mode-S code 71C531?
71C531 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8531.
Where is Mode-S 71C531 registered?
Mode-S code 71C531 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 71C531 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 20:50 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C531, octal 34342461, decimal 7,456,049.
What flights does 71C531 operate?
Mode-S 71C531 has broadcast 20 distinct callsigns, including KAL656, KAL2174, KAL2171, KAL655, KAL2173.