sensors Mode-S transponder

71C577

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

Currently assigned to HL8577 · BOEING 787-10 Dreamliner

Hex
71C577
Octal
34342567
Decimal
7,456,119
Country
KR
Tail
HL8577
Type
B78X
No current signal · last broadcast 15h ago
Flights observed
13
Distinct callsigns
4
Country
KR
Last broadcast
15h ago

Last known position

Most recent position reported by Mode-S 71C577.

Country allocation

The ICAO 24-bit address 71C577 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 4 distinct

Callsign Airline Flights Last seen
KAL2103 - 5 2026-04-14
KAL2104 - 3 2026-04-13
KAL2102 - 3 2026-04-14
KAL2101 - 2 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-14 KAL2103 - Apr 14, 09:10 UTCApr 14, 09:30 UTC20m
2026-04-14 KAL2103 - Apr 14, 07:40 UTCApr 14, 09:05 UTC1h 25m
2026-04-14 KAL2102 - Apr 14, 05:20 UTCApr 14, 05:50 UTC30m
2026-04-13 KAL2104 - Apr 13, 12:40 UTCApr 13, 13:10 UTC30m
2026-04-13 KAL2104 - Apr 13, 11:55 UTCApr 13, 13:10 UTC1h 15m
2026-04-13 KAL2104 - Apr 13, 11:15 UTCApr 13, 12:00 UTC45m
2026-04-13 KAL2103 - Apr 13, 08:35 UTCApr 13, 09:30 UTC55m
2026-04-13 KAL2103 - Apr 13, 07:55 UTCApr 13, 09:30 UTC1h 35m
2026-04-13 KAL2103 - Apr 13, 07:40 UTCApr 13, 08:10 UTC30m
2026-04-13 KAL2102 - Apr 13, 04:20 UTCApr 13, 05:50 UTC1h 30m
2026-04-13 KAL2102 - Apr 13, 04:00 UTCApr 13, 04:15 UTC15m
2026-04-13 KAL2101 - Apr 13, 01:25 UTCApr 13, 02:20 UTC55m
2026-04-13 KAL2101 - Apr 13, 00:20 UTCApr 13, 00:50 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 HL8577 page for operator, model, and routing details .

Mode-S 71C577 frequently asked

What is Mode-S code 71C577?
71C577 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8577.
Where is Mode-S 71C577 registered?
Mode-S code 71C577 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 71C577 broadcasting right now?
No active broadcast right now. Last signal was 15h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C577, octal 34342567, decimal 7,456,119.
What flights does 71C577 operate?
Mode-S 71C577 has broadcast 4 distinct callsigns, including KAL2103, KAL2104, KAL2102, KAL2101.