Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

71C557

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

Currently assigned to HL8557 · AIRBUS A-321neo

Hex
71C557
Octal
34342527
Decimal
7,456,087
Country
KR
Tail
HL8557
Type
A21N
Broadcasting now · callsign KAL1822 · 10,100 ft
Flights observed
218
Distinct callsigns
20
Country
KR
Last broadcast
7m ago

Current position

71C557 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 71C557 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
KAL1822 Korean Air 14 2026-05-30
KAL1174 Korean Air 14 2026-05-30
KAL1045 Korean Air 14 2026-05-29
KAL1819 Korean Air 13 2026-05-30
KAL1328 Korean Air 11 2026-05-29
KAL1205 Korean Air 11 2026-05-29
KAL706 Korean Air 6 2026-04-20
KAL2147 Korean Air 6 2026-05-03
KAL2016 Korean Air 6 2026-05-10
KAL2005 Korean Air 6 2026-04-25
KAL792 Korean Air 5 2026-05-15
KAL705 Korean Air 5 2026-04-19
KAL689 Korean Air 5 2026-04-29
KAL2180 Korean Air 5 2026-05-13
KAL2172 Korean Air 5 2026-05-06
KAL2148 Korean Air 5 2026-05-12
KAL2015 Korean Air 5 2026-05-10
KAL2006 Korean Air 5 2026-04-25
KAL2179 Korean Air 4 2026-05-13
KAL791 Korean Air 3 2026-05-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 KAL1822 PUS → GMP May 30, 07:30 UTCMay 30, 07:45 UTC15m
2026-05-30 KAL1819 GMP → PUS May 30, 05:15 UTCMay 30, 05:40 UTC25m
2026-05-30 KAL1174 CJU → GMP May 30, 01:55 UTCMay 30, 02:30 UTC35m
2026-05-29 KAL1045 GMP → CJU May 29, 23:30 UTCMay 29, 23:55 UTC25m
2026-05-29 KAL1328 CJU → GMP May 29, 12:20 UTCMay 29, 12:50 UTC30m
2026-05-29 KAL1205 GMP → CJU May 29, 10:00 UTCMay 29, 10:25 UTC25m
2026-05-29 KAL1822 PUS → GMP May 29, 07:25 UTCMay 29, 07:55 UTC30m
2026-05-29 KAL1819 GMP → PUS May 29, 05:15 UTCMay 29, 05:45 UTC30m
2026-05-29 KAL1174 CJU → GMP May 29, 02:05 UTCMay 29, 02:45 UTC40m
2026-05-28 KAL1045 GMP → CJU May 28, 23:35 UTCMay 29, 00:00 UTC25m
2026-05-28 KAL1328 CJU → GMP May 28, 12:25 UTCMay 28, 13:00 UTC35m
2026-05-28 KAL1205 GMP → CJU May 28, 10:05 UTCMay 28, 10:30 UTC25m
2026-05-28 KAL1822 PUS → GMP May 28, 07:20 UTCMay 28, 07:55 UTC35m
2026-05-28 KAL1819 GMP → PUS May 28, 05:15 UTCMay 28, 05:45 UTC30m
2026-05-28 KAL1174 CJU → GMP May 28, 02:00 UTCMay 28, 02:30 UTC30m
2026-05-27 KAL1045 GMP → CJU May 27, 23:35 UTCMay 28, 00:00 UTC25m
2026-05-27 KAL1328 CJU → GMP May 27, 12:15 UTCMay 27, 12:45 UTC30m
2026-05-27 KAL1205 GMP → CJU May 27, 10:05 UTCMay 27, 10:30 UTC25m
2026-05-27 KAL1822 PUS → GMP May 27, 07:15 UTCMay 27, 07:50 UTC35m
2026-05-27 KAL1819 GMP → PUS May 27, 05:24 UTCMay 27, 05:49 UTC25m
2026-05-27 KAL1174 CJU → GMP May 27, 02:14 UTCMay 27, 02:49 UTC35m
2026-05-26 KAL1045 GMP → CJU May 26, 23:45 UTCMay 27, 00:10 UTC25m
2026-05-26 KAL1328 CJU → GMP May 26, 12:24 UTCMay 26, 12:54 UTC30m
2026-05-26 KAL1205 GMP → CJU May 26, 10:10 UTCMay 26, 10:39 UTC30m
2026-05-26 KAL1822 PUS → GMP May 26, 07:15 UTCMay 26, 07:49 UTC35m
2026-05-26 KAL1819 GMP → PUS May 26, 05:25 UTCMay 26, 05:54 UTC30m
2026-05-26 KAL1174 CJU → GMP May 26, 02:04 UTCMay 26, 02:29 UTC25m
2026-05-25 KAL1045 GMP → CJU May 25, 23:30 UTCMay 25, 23:54 UTC25m
2026-05-25 KAL1830 PUS → GMP May 25, 10:45 UTCMay 25, 11:15 UTC30m
2026-05-25 KAL1827 GMP → PUS May 25, 08:50 UTCMay 25, 09:20 UTC30m
2026-05-25 KAL1822 PUS → GMP May 25, 07:15 UTCMay 25, 07:50 UTC35m
2026-05-25 KAL1819 GMP → PUS May 25, 05:15 UTCMay 25, 05:45 UTC30m
2026-05-25 KAL1174 CJU → GMP May 25, 01:55 UTCMay 25, 02:35 UTC40m
2026-05-24 KAL1045 GMP → CJU May 24, 23:45 UTCMay 24, 23:46 UTC1m
2026-05-24 KAL1328 CJU → GMP May 24, 12:20 UTCMay 24, 12:45 UTC25m
2026-05-24 KAL1205 GMP → CJU May 24, 10:00 UTCMay 24, 10:25 UTC25m
2026-05-24 KAL1822 PUS → GMP May 24, 07:15 UTCMay 24, 07:45 UTC30m
2026-05-24 KAL1819 GMP → PUS May 24, 05:20 UTCMay 24, 05:45 UTC25m
2026-05-24 KAL1174 CJU → GMP May 24, 02:15 UTCMay 24, 02:45 UTC30m
2026-05-23 KAL1045 GMP → CJU May 23, 23:50 UTCMay 24, 00:15 UTC25m
2026-05-23 KAL1834 PUS → GMP May 23, 12:35 UTCMay 23, 13:10 UTC35m
2026-05-23 KAL1831 GMP → PUS May 23, 10:40 UTCMay 23, 11:05 UTC25m
2026-05-23 KAL1822 PUS → GMP May 23, 07:20 UTCMay 23, 07:55 UTC35m
2026-05-23 KAL1819 GMP → PUS May 23, 05:20 UTCMay 23, 05:50 UTC30m
2026-05-23 KAL1174 CJU → GMP May 23, 02:05 UTCMay 23, 02:45 UTC39m
2026-05-22 KAL1045 GMP → CJU May 22, 23:35 UTCMay 23, 00:00 UTC25m
2026-05-22 KAL1834 PUS → GMP May 22, 12:35 UTCMay 22, 13:10 UTC35m
2026-05-22 KAL1831 GMP → PUS May 22, 10:45 UTCMay 22, 11:15 UTC30m
2026-05-22 KAL1822 PUS → GMP May 22, 07:10 UTCMay 22, 07:45 UTC35m
2026-05-22 KAL1819 GMP → PUS May 22, 05:20 UTCMay 22, 05:45 UTC25m

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 HL8557 page for operator, model, and routing details .

Mode-S 71C557 frequently asked

What is Mode-S code 71C557?
71C557 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8557.
Where is Mode-S 71C557 registered?
Mode-S code 71C557 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 71C557 broadcasting right now?
Yes. Mode-S 71C557 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C557, octal 34342527, decimal 7,456,087.
What flights does 71C557 operate?
Mode-S 71C557 has broadcast 20 distinct callsigns, including KAL1822, KAL1174, KAL1045, KAL1819, KAL1328.