sensors Mode-S transponder

71C709

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

Currently assigned to HL8709 · AIRBUS A-330-200

Hex
71C709
Octal
34343411
Decimal
7,456,521
Country
KR
Tail
HL8709
Type
A332
Broadcasting now · callsign PTA501 · 39,000 ft
Flights observed
9
Distinct callsigns
5
Country
KR
Last broadcast
17h ago

Current position

71C709 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 71C709 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 5 distinct

Callsign Airline Flights Last seen
PTA201 - 3 2026-04-13
PTA504 - 2 2026-04-14
PTA202 - 2 2026-04-13
PTA502 - 1 2026-04-13
PTA501 Ptarmigan Airways 1 2026-04-13

Recent flights last 9

DateFlightRouteTakeoffLandingDuration
2026-04-14 PTA504 - Apr 14, 07:10 UTCApr 14, 08:55 UTC1h 45m
2026-04-14 PTA504 - Apr 14, 06:50 UTCApr 14, 07:10 UTC20m
2026-04-13 PTA202 - Apr 13, 16:55 UTCApr 13, 19:45 UTC2h 50m
2026-04-13 PTA201 - Apr 13, 12:20 UTCApr 13, 12:50 UTC30m
2026-04-13 PTA201 - Apr 13, 11:55 UTCApr 13, 12:50 UTC55m
2026-04-13 PTA201 - Apr 13, 09:55 UTCApr 13, 12:15 UTC2h 20m
2026-04-13 PTA502 - Apr 13, 04:50 UTCApr 13, 06:55 UTC2h 5m
2026-04-13 PTA501 ICN → NRT Apr 13, 01:10 UTCApr 13, 03:00 UTC1h 50m
2026-04-12 PTA202 - Apr 12, 18:10 UTCApr 12, 20:15 UTC2h 5m

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 HL8709 page for operator, model, and routing details .

Mode-S 71C709 frequently asked

What is Mode-S code 71C709?
71C709 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8709.
Where is Mode-S 71C709 registered?
Mode-S code 71C709 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 71C709 broadcasting right now?
Yes. Mode-S 71C709 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C709, octal 34343411, decimal 7,456,521.
What flights does 71C709 operate?
Mode-S 71C709 has broadcast 5 distinct callsigns, including PTA201, PTA504, PTA202, PTA502, PTA501.