Apparatus

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sensors Mode-S transponder

71C540

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

Currently assigned to HL8540 · AIRBUS A-320

Hex
71C540
Octal
34342500
Decimal
7,456,064
Country
KR
Tail
HL8540
Type
A320
No current signal · last broadcast Jul 26, 21:35 UTC
Flights observed
540
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 21:35 UTC

Last known position

Most recent position reported by Mode-S 71C540.

Country allocation

The ICAO 24-bit address 71C540 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
EOK351 Aero K 30 2026-07-24
EOK352 Aero K 26 2026-07-23
EOK511 Aero K 25 2026-07-25
EOK512 Aero K 23 2026-07-25
EOK318 Aero K 22 2026-07-24
EOK332 Aero K 21 2026-07-24
EOK331 - 21 2026-07-24
EOK317 Aero K 21 2026-07-24
EOK341 Aero K 20 2026-07-25
EOK614 - 18 2026-07-21
EOK613 Aero K 18 2026-07-21
EOK610 Aero K 18 2026-07-21
EOK609 Aero K 18 2026-07-21
EOK342 Aero K 18 2026-07-25
EOK324 - 17 2026-07-12
EOK393 Aero K 16 2026-07-19
EOK323 - 15 2026-07-12
EOK394 Aero K 13 2026-07-18
EOK374 - 13 2026-07-25
EOK373 - 13 2026-07-26

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 EOK8973 - Jul 26, 13:40 UTCJul 26, 21:35 UTC7h 55m
2026-07-26 EOK353 OBO → CJJ Jul 26, 09:10 UTCJul 26, 11:35 UTC2h 25m
2026-07-26 EOK354 CJJ → OBO Jul 26, 05:05 UTCJul 26, 07:10 UTC2h 6m
2026-07-26 EOK373 - Jul 26, 03:05 UTCJul 26, 03:50 UTC45m
2026-07-25 EOK374 - Jul 25, 23:50 UTCJul 26, 00:35 UTC45m
2026-07-25 EOK341 NGO → CJJ Jul 25, 11:40 UTCJul 25, 12:50 UTC1h 10m
2026-07-25 EOK342 CJJ → NGO Jul 25, 08:50 UTCJul 25, 10:05 UTC1h 15m
2026-07-25 EOK512 TPE → CJJ Jul 25, 05:35 UTCJul 25, 07:40 UTC2h 5m
2026-07-25 EOK511 CJJ → TPE Jul 25, 03:20 UTCJul 25, 03:40 UTC20m
2026-07-25 EOK511 CJJ → TPE Jul 25, 01:40 UTCJul 25, 02:15 UTC35m
2026-07-24 EOK331 - Jul 24, 23:35 UTCJul 25, 00:20 UTC45m
2026-07-24 EOK332 CJJ → FUK Jul 24, 21:45 UTCJul 24, 22:20 UTC35m
2026-07-24 EOK317 KIX → CJJ Jul 24, 10:15 UTCJul 24, 11:15 UTC1h 0m
2026-07-24 EOK318 CJJ → KIX Jul 24, 06:55 UTCJul 24, 08:10 UTC1h 15m
2026-07-24 EOK351 CTS → CJJ Jul 24, 03:15 UTCJul 24, 05:30 UTC2h 15m
2026-07-23 EOK352 CJJ → CTS Jul 23, 23:40 UTCJul 24, 01:55 UTC2h 15m
2026-07-23 EOK317 KIX → CJJ Jul 23, 10:15 UTCJul 23, 11:25 UTC1h 10m
2026-07-23 EOK318 CJJ → KIX Jul 23, 07:05 UTCJul 23, 08:15 UTC1h 10m
2026-07-23 EOK391 NRT → CJJ Jul 23, 02:00 UTCJul 23, 03:45 UTC1h 45m
2026-07-22 EOK392 - Jul 22, 22:50 UTCJul 23, 00:40 UTC1h 50m
2026-07-22 EOK422 UBN → CJJ Jul 22, 20:45 UTCJul 22, 21:25 UTC40m
2026-07-22 EOK421 CJJ → UBN Jul 22, 13:25 UTCJul 22, 15:10 UTC1h 45m
2026-07-22 EOK353 - Jul 22, 11:15 UTCJul 22, 11:40 UTC25m
2026-07-22 EOK354 CJJ → OBO Jul 22, 05:10 UTCJul 22, 10:25 UTC5h 15m
2026-07-22 EOK373 - Jul 22, 03:00 UTCJul 22, 03:35 UTC35m
2026-07-21 EOK374 - Jul 21, 23:50 UTCJul 22, 00:35 UTC45m
2026-07-21 EOK614 - Jul 21, 13:00 UTCJul 21, 13:30 UTC30m
2026-07-21 EOK613 CJJ → CJU Jul 21, 09:50 UTCJul 21, 10:20 UTC30m
2026-07-21 EOK610 CJU → CJJ Jul 21, 08:10 UTCJul 21, 08:40 UTC30m
2026-07-21 EOK609 CJJ → CJU Jul 21, 06:05 UTCJul 21, 06:35 UTC30m
2026-07-20 EOK317 KIX → CJJ Jul 20, 10:15 UTCJul 20, 11:35 UTC1h 20m
2026-07-20 EOK318 CJJ → KIX Jul 20, 07:05 UTCJul 20, 08:25 UTC1h 20m
2026-07-20 EOK351 CTS → CJJ Jul 20, 03:20 UTCJul 20, 05:40 UTC2h 20m
2026-07-20 EOK352 CJJ → CTS Jul 20, 00:05 UTCJul 20, 02:10 UTC2h 5m
2026-07-19 EOK305 - Jul 19, 11:55 UTCJul 19, 13:00 UTC1h 5m
2026-07-19 EOK306 - Jul 19, 09:05 UTCJul 19, 10:25 UTC1h 20m
2026-07-19 EOK385 HIJ → CJJ Jul 19, 06:55 UTCJul 19, 07:50 UTC55m
2026-07-19 EOK386 CJJ → HIJ Jul 19, 04:40 UTCJul 19, 05:35 UTC55m
2026-07-19 EOK393 OKA → CJJ Jul 19, 01:00 UTCJul 19, 02:40 UTC1h 40m
2026-07-18 EOK394 CJJ → OKA Jul 18, 22:10 UTCJul 18, 23:45 UTC1h 35m
2026-07-18 EOK317 - Jul 18, 10:25 UTCJul 18, 11:35 UTC1h 10m
2026-07-18 EOK318 - Jul 18, 07:55 UTCJul 18, 09:20 UTC1h 25m
2026-07-18 EOK351 - Jul 18, 03:20 UTCJul 18, 05:35 UTC2h 15m
2026-07-17 EOK352 - Jul 17, 23:50 UTCJul 18, 02:00 UTC2h 10m
2026-07-17 EOK317 - Jul 17, 10:15 UTCJul 17, 11:25 UTC1h 10m
2026-07-17 EOK318 - Jul 17, 07:14 UTCJul 17, 08:30 UTC1h 15m
2026-07-17 EOK351 - Jul 17, 03:10 UTCJul 17, 05:25 UTC2h 15m
2026-07-16 EOK352 - Jul 16, 23:44 UTCJul 17, 02:05 UTC2h 20m
2026-07-16 EOK8973 - Jul 16, 13:45 UTCJul 16, 21:30 UTC7h 45m
2026-07-16 EOK317 - Jul 16, 10:15 UTCJul 16, 11:20 UTC1h 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 HL8540 page for operator, model, and routing details .

Mode-S 71C540 frequently asked

What is Mode-S code 71C540?
71C540 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8540.
Where is Mode-S 71C540 registered?
Mode-S code 71C540 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 71C540 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:35 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C540, octal 34342500, decimal 7,456,064.
What flights does 71C540 operate?
Mode-S 71C540 has broadcast 20 distinct callsigns, including EOK351, EOK352, EOK511, EOK512, EOK318.