sensors Mode-S transponder

71C559

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

Currently assigned to HL8559 · AIRBUS A-321neo

Hex
71C559
Octal
34342531
Decimal
7,456,089
Country
KR
Tail
HL8559
Type
A21N
No current signal · last broadcast 14h ago
Flights observed
12
Distinct callsigns
7
Country
KR
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 71C559.

Country allocation

The ICAO 24-bit address 71C559 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 7 distinct

Callsign Airline Flights Last seen
KAL708 - 3 2026-04-13
KAL707 - 3 2026-04-13
KAL737 - 2 2026-04-13
KAL738 - 1 2026-04-13
KAL2189 Korean Air 1 2026-04-13
KAL2180 - 1 2026-04-14
KAL2179 - 1 2026-04-14

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-14 KAL2180 - Apr 14, 10:25 UTCApr 14, 11:05 UTC40m
2026-04-14 KAL2179 - Apr 14, 07:45 UTCApr 14, 08:40 UTC55m
2026-04-13 KAL2189 ICN → KMQ Apr 13, 23:00 UTCApr 13, 23:30 UTC30m
2026-04-13 KAL738 - Apr 13, 17:30 UTCApr 13, 18:55 UTC1h 25m
2026-04-13 KAL737 - Apr 13, 12:20 UTCApr 13, 13:10 UTC50m
2026-04-13 KAL737 - Apr 13, 12:05 UTCApr 13, 12:15 UTC10m
2026-04-13 KAL708 - Apr 13, 08:55 UTCApr 13, 09:30 UTC35m
2026-04-13 KAL708 - Apr 13, 07:55 UTCApr 13, 09:30 UTC1h 35m
2026-04-13 KAL708 - Apr 13, 07:30 UTCApr 13, 08:15 UTC45m
2026-04-13 KAL707 - Apr 13, 05:05 UTCApr 13, 06:00 UTC55m
2026-04-13 KAL707 - Apr 13, 04:20 UTCApr 13, 04:30 UTC10m
2026-04-13 KAL707 - Apr 13, 04:00 UTCApr 13, 04:15 UTC15m

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 HL8559 page for operator, model, and routing details .

Mode-S 71C559 frequently asked

What is Mode-S code 71C559?
71C559 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8559.
Where is Mode-S 71C559 registered?
Mode-S code 71C559 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 71C559 broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C559, octal 34342531, decimal 7,456,089.
What flights does 71C559 operate?
Mode-S 71C559 has broadcast 7 distinct callsigns, including KAL708, KAL707, KAL737, KAL738, KAL2189.