Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

71C591

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

Currently assigned to HL8591 · AIRBUS A-321neo

Hex
71C591
Octal
34342621
Decimal
7,456,145
Country
KR
Tail
HL8591
Type
A21N
No current signal · last broadcast 5h ago
Flights observed
159
Distinct callsigns
20
Country
KR
Last broadcast
5h ago

Last known position

Most recent position reported by Mode-S 71C591.

Country allocation

The ICAO 24-bit address 71C591 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
KAL2174 Korean Air 9 2026-05-30
KAL2171 Korean Air 9 2026-05-30
KAL2173 Korean Air 7 2026-05-30
KAL2172 Korean Air 7 2026-05-30
KAL852 Korean Air 6 2026-05-27
KAL737 Korean Air 5 2026-05-24
KAL2065 Korean Air 5 2026-05-27
KAL851 Korean Air 4 2026-05-26
KAL770 Korean Air 4 2026-05-11
KAL769 Korean Air 4 2026-05-11
KAL738 Korean Air 4 2026-05-24
KAL712 Korean Air 4 2026-05-16
KAL711 Korean Air 4 2026-05-16
KAL2066 Korean Air 4 2026-05-27
KAL101 Korean Air 4 2026-05-03
KAL742 Korean Air 3 2026-05-20
KAL741 Korean Air 3 2026-05-20
KAL689 Korean Air 3 2026-05-29
KAL2180 Korean Air 3 2026-05-18
KAL2179 Korean Air 3 2026-05-18

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 KAL2174 UKB → ICN May 30, 10:15 UTCMay 30, 11:45 UTC1h 30m
2026-05-30 KAL2173 ICN → UKB May 30, 07:10 UTCMay 30, 08:25 UTC1h 15m
2026-05-30 KAL2172 UKB → ICN May 30, 03:05 UTCMay 30, 04:40 UTC1h 35m
2026-05-30 KAL2171 ICN → UKB May 30, 00:25 UTCMay 30, 01:35 UTC1h 10m
2026-05-29 KAL689 ICN → PNH May 29, 10:30 UTCMay 29, 22:40 UTC12h 10m
2026-05-29 KAL792 OIT → ICN May 29, 06:35 UTCMay 29, 07:10 UTC35m
2026-05-29 KAL791 ICN → FUK May 29, 02:35 UTCMay 29, 03:05 UTC30m
2026-05-28 KAL163 ICN → DYG May 28, 11:05 UTCMay 28, 18:10 UTC7h 5m
2026-05-27 KAL852 PEK → ICN May 27, 11:40 UTCMay 27, 12:00 UTC20m
2026-05-27 KAL852 PEK → ICN May 27, 10:40 UTCMay 27, 10:55 UTC15m
2026-05-27 KAL2065 CJU → PEK May 27, 07:15 UTCMay 27, 07:35 UTC20m
2026-05-27 KAL2066 PEK → CJU May 27, 04:09 UTCMay 27, 04:24 UTC15m
2026-05-26 KAL851 ICN → PEK May 26, 23:39 UTCMay 27, 00:04 UTC25m
2026-05-26 KAL2006 HKG → ICN May 26, 10:20 UTCMay 26, 13:34 UTC3h 15m
2026-05-26 KAL2005 ICN → HKG May 26, 04:50 UTCMay 26, 07:55 UTC3h 5m
2026-05-26 KAL656 BKK → ICN May 26, 00:49 UTCMay 26, 01:14 UTC25m
2026-05-25 KAL656 BKK → ICN May 25, 20:15 UTCMay 25, 23:40 UTC3h 25m
2026-05-25 KAL655 ICN → BKK May 25, 12:50 UTCMay 25, 18:20 UTC5h 30m
2026-05-25 KAL726 KIX → ICN May 25, 09:45 UTCMay 25, 11:05 UTC1h 20m
2026-05-25 KAL725 ICN → KIX May 25, 06:30 UTCMay 25, 08:00 UTC1h 30m
2026-05-25 KAL842 TAO → ICN May 25, 02:35 UTCMay 25, 03:10 UTC35m
2026-05-24 KAL841 ICN → TAO May 24, 23:15 UTCMay 24, 23:46 UTC31m
2026-05-24 KAL738 KIX → ICN May 24, 17:25 UTCMay 24, 18:45 UTC1h 20m
2026-05-24 KAL737 ICN → KIX May 24, 12:35 UTCMay 24, 13:35 UTC1h 0m
2026-05-24 KAL737 ICN → KIX May 24, 12:15 UTCMay 24, 12:30 UTC15m
2026-05-24 KAL142 XIY → ICN May 24, 07:00 UTCMay 24, 07:30 UTC30m
2026-05-24 KAL141 ICN → XIY May 24, 00:45 UTCMay 24, 01:05 UTC20m
2026-05-23 KAL486 PQC → ICN May 23, 10:30 UTCMay 23, 22:50 UTC12h 20m
2026-05-23 KAL874 - May 23, 07:25 UTCMay 23, 07:45 UTC20m
2026-05-23 KAL873 - May 23, 04:40 UTCMay 23, 05:05 UTC25m
2026-05-23 KAL706 NRT → ICN May 23, 00:35 UTCMay 23, 02:35 UTC2h 0m
2026-05-22 KAL705 ICN → NRT May 22, 09:50 UTCMay 22, 11:50 UTC2h 0m
2026-05-21 KAL892 PVG → ICN May 21, 10:50 UTCMay 22, 02:45 UTC15h 55m
2026-05-20 KAL690 PNH → ICN May 20, 10:20 UTCMay 20, 21:45 UTC11h 25m
2026-05-20 KAL742 NGO → ICN May 20, 05:00 UTCMay 20, 06:35 UTC1h 35m
2026-05-20 KAL741 ICN → NGO May 20, 02:00 UTCMay 20, 03:20 UTC1h 20m
2026-05-19 KAL2174 UKB → ICN May 19, 10:10 UTCMay 19, 11:30 UTC1h 20m
2026-05-19 KAL2173 ICN → UKB May 19, 07:10 UTCMay 19, 08:35 UTC1h 25m
2026-05-19 KAL2172 UKB → ICN May 19, 03:05 UTCMay 19, 04:25 UTC1h 20m
2026-05-19 KAL2171 ICN → UKB May 19, 00:20 UTCMay 19, 01:35 UTC1h 15m
2026-05-18 KAL146 CSX → ICN May 18, 13:50 UTCMay 18, 20:55 UTC7h 4m
2026-05-18 KAL2180 KOJ → ICN May 18, 10:25 UTCMay 18, 11:15 UTC50m
2026-05-18 KAL2179 ICN → KOJ May 18, 07:40 UTCMay 18, 08:35 UTC55m
2026-05-17 KAL892 PVG → ICN May 17, 10:20 UTCMay 18, 02:55 UTC16h 35m
2026-05-16 KAL712 NRT → ICN May 16, 08:31 UTCMay 16, 10:16 UTC1h 45m
2026-05-16 KAL711 ICN → NRT May 16, 04:15 UTCMay 16, 06:25 UTC2h 11m
2026-05-15 KAL2006 HKG → ICN May 15, 10:50 UTCMay 15, 13:55 UTC3h 5m
2026-05-15 KAL2005 ICN → HKG May 15, 07:50 UTCMay 15, 08:10 UTC20m
2026-05-15 KAL2005 ICN → HKG May 15, 04:50 UTCMay 15, 07:15 UTC2h 25m
2026-05-15 KAL1408 PUS → ICN May 15, 01:55 UTCMay 15, 02:25 UTC30m

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 HL8591 page for operator, model, and routing details .

Mode-S 71C591 frequently asked

What is Mode-S code 71C591?
71C591 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8591.
Where is Mode-S 71C591 registered?
Mode-S code 71C591 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 71C591 broadcasting right now?
No active broadcast right now. Last signal was 5h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C591, octal 34342621, decimal 7,456,145.
What flights does 71C591 operate?
Mode-S 71C591 has broadcast 20 distinct callsigns, including KAL2174, KAL2171, KAL2173, KAL2172, KAL852.