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
No current signal · last broadcast Jul 26, 11:55 UTC
Flights observed
557
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 11:55 UTC

Last known position

Most recent position reported by Mode-S 71C557.

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
KAL1045 Korean Air 71 2026-07-25
KAL1174 Korean Air 70 2026-07-26
KAL1822 Korean Air 67 2026-07-26
KAL1819 Korean Air 67 2026-07-26
KAL1830 Korean Air 44 2026-07-26
KAL1827 Korean Air 44 2026-07-26
KAL1328 Korean Air 23 2026-06-10
KAL1205 Korean Air 23 2026-06-10
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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 KAL1830 PUS → GMP Jul 26, 10:40 UTCJul 26, 11:20 UTC40m
2026-07-26 KAL1827 GMP → PUS Jul 26, 09:00 UTCJul 26, 09:40 UTC40m
2026-07-26 KAL1822 PUS → GMP Jul 26, 07:15 UTCJul 26, 08:00 UTC45m
2026-07-26 KAL1819 GMP → PUS Jul 26, 05:30 UTCJul 26, 06:10 UTC40m
2026-07-26 KAL1174 CJU → GMP Jul 26, 01:50 UTCJul 26, 02:35 UTC45m
2026-07-25 KAL1045 GMP → CJU Jul 25, 23:35 UTCJul 26, 00:10 UTC35m
2026-07-25 KAL1830 PUS → GMP Jul 25, 10:55 UTCJul 25, 11:40 UTC45m
2026-07-25 KAL1827 GMP → PUS Jul 25, 09:00 UTCJul 25, 09:40 UTC40m
2026-07-25 KAL1820 PUS → GMP Jul 25, 05:40 UTCJul 25, 06:25 UTC45m
2026-07-25 KAL1815 GMP → PUS Jul 25, 03:45 UTCJul 25, 04:25 UTC40m
2026-07-25 KAL1174 CJU → GMP Jul 25, 01:55 UTCJul 25, 02:35 UTC40m
2026-07-24 KAL1045 GMP → CJU Jul 24, 23:35 UTCJul 25, 00:10 UTC35m
2026-07-24 KAL1830 PUS → GMP Jul 24, 11:35 UTCJul 24, 12:15 UTC40m
2026-07-24 KAL1827 GMP → PUS Jul 24, 09:30 UTCJul 24, 10:10 UTC40m
2026-07-24 KAL1822 PUS → GMP Jul 24, 07:25 UTCJul 24, 08:10 UTC45m
2026-07-24 KAL1819 GMP → PUS Jul 24, 05:25 UTCJul 24, 06:20 UTC55m
2026-07-24 KAL1174 CJU → GMP Jul 24, 01:55 UTCJul 24, 02:35 UTC40m
2026-07-23 KAL1045 GMP → CJU Jul 23, 23:40 UTCJul 24, 00:15 UTC35m
2026-07-23 KAL1830 PUS → GMP Jul 23, 10:45 UTCJul 23, 11:30 UTC45m
2026-07-23 KAL1827 GMP → PUS Jul 23, 09:00 UTCJul 23, 09:40 UTC40m
2026-07-23 KAL1822 PUS → GMP Jul 23, 07:15 UTCJul 23, 07:55 UTC40m
2026-07-23 KAL1819 GMP → PUS Jul 23, 05:20 UTCJul 23, 06:05 UTC45m
2026-07-23 KAL1174 CJU → GMP Jul 23, 01:55 UTCJul 23, 02:40 UTC45m
2026-07-22 KAL1045 GMP → CJU Jul 22, 23:35 UTCJul 23, 00:10 UTC35m
2026-07-22 KAL1830 PUS → GMP Jul 22, 11:10 UTCJul 22, 11:40 UTC30m
2026-07-22 KAL1819 GMP → PUS Jul 22, 05:20 UTCJul 22, 05:25 UTC5m
2026-07-22 KAL1174 CJU → GMP Jul 22, 01:50 UTCJul 22, 02:25 UTC35m
2026-07-21 KAL1045 GMP → CJU Jul 21, 23:40 UTCJul 22, 00:10 UTC30m
2026-07-21 KAL1830 PUS → GMP Jul 21, 11:10 UTCJul 21, 11:50 UTC40m
2026-07-21 KAL1827 GMP → PUS Jul 21, 09:25 UTCJul 21, 10:05 UTC40m
2026-07-21 KAL1822 PUS → GMP Jul 21, 07:25 UTCJul 21, 08:10 UTC45m
2026-07-21 KAL1819 GMP → PUS Jul 21, 05:25 UTCJul 21, 06:15 UTC50m
2026-07-21 KAL1174 CJU → GMP Jul 21, 02:10 UTCJul 21, 02:50 UTC40m
2026-07-20 KAL1045 GMP → CJU Jul 20, 23:40 UTCJul 21, 00:15 UTC35m
2026-07-20 KAL1830 PUS → GMP Jul 20, 10:50 UTCJul 20, 11:30 UTC40m
2026-07-20 KAL1827 GMP → PUS Jul 20, 09:05 UTCJul 20, 09:50 UTC45m
2026-07-20 KAL1822 PUS → GMP Jul 20, 07:15 UTCJul 20, 08:00 UTC45m
2026-07-20 KAL1819 GMP → PUS Jul 20, 05:20 UTCJul 20, 06:00 UTC40m
2026-07-20 KAL1174 CJU → GMP Jul 20, 02:10 UTCJul 20, 02:45 UTC35m
2026-07-19 KAL1045 - Jul 19, 23:35 UTCJul 20, 00:10 UTC35m
2026-07-19 KAL1830 PUS → GMP Jul 19, 10:35 UTCJul 19, 11:10 UTC35m
2026-07-19 KAL1827 GMP → PUS Jul 19, 08:55 UTCJul 19, 09:35 UTC40m
2026-07-19 KAL1822 PUS → GMP Jul 19, 07:20 UTCJul 19, 07:55 UTC35m
2026-07-19 KAL1819 GMP → PUS Jul 19, 05:20 UTCJul 19, 06:15 UTC55m
2026-07-19 KAL1174 CJU → GMP Jul 19, 02:00 UTCJul 19, 02:45 UTC45m
2026-07-18 KAL1045 - Jul 18, 23:45 UTCJul 19, 00:20 UTC35m
2026-07-18 KAL1830 PUS → GMP Jul 18, 10:40 UTCJul 18, 11:15 UTC35m
2026-07-18 KAL1827 GMP → PUS Jul 18, 09:00 UTCJul 18, 09:40 UTC40m
2026-07-18 KAL1822 PUS → GMP Jul 18, 07:10 UTCJul 18, 07:55 UTC45m
2026-07-18 KAL1819 GMP → PUS Jul 18, 05:15 UTCJul 18, 05:55 UTC40m

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?
No active broadcast right now. Last signal was Jul 26, 11:55 UTC.
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 KAL1045, KAL1174, KAL1822, KAL1819, KAL1830.