Apparatus

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sensors Mode-S transponder

71C544

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

Currently assigned to HL8544 · BOEING 737 MAX 8

Hex
71C544
Octal
34342504
Decimal
7,456,068
Country
KR
Tail
HL8544
Type
B38M
No current signal · last broadcast 1h ago
Flights observed
573
Distinct callsigns
20
Country
KR
Last broadcast
1h ago

Last known position

Most recent position reported by Mode-S 71C544.

Country allocation

The ICAO 24-bit address 71C544 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
ESR782 - 23 2026-07-12
ESR781 - 19 2026-07-12
ESR233 - 19 2026-07-12
ESR716 - 18 2026-07-12
ESR711 - 18 2026-07-12
ESR224 - 17 2026-07-12
ESR223 - 17 2026-07-12
ESR216 - 14 2026-07-12
ESR213 - 14 2026-07-12
ESR282 - 12 2026-07-08
ESR205 - 11 2026-07-08
ESR208 - 10 2026-07-11
ESR281 - 9 2026-07-08
ESR214 - 9 2026-07-08
ESR206 - 9 2026-06-30
ESR984 Eastar Jet 8 2026-06-16
ESR887 - 8 2026-06-27
ESR536 Eastar Jet 8 2026-05-20
ESR222 - 8 2026-07-08
ESR221 - 8 2026-07-08

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 ESR944 - Jul 14, 08:15 UTCJul 14, 08:45 UTC30m
2026-07-14 ESR943 - Jul 14, 06:00 UTCJul 14, 06:25 UTC25m
2026-07-14 ESR914 KIX → PUS Jul 14, 03:35 UTCJul 14, 04:40 UTC1h 5m
2026-07-14 ESR913 PUS → KIX Jul 14, 01:15 UTCJul 14, 02:15 UTC1h 0m
2026-07-13 ESR988 - Jul 13, 20:25 UTCJul 13, 21:10 UTC45m
2026-07-13 ESR988 - Jul 13, 18:55 UTCJul 13, 19:25 UTC30m
2026-07-13 ESR987 PUS → TPE Jul 13, 13:40 UTCJul 13, 15:40 UTC2h 0m
2026-07-13 ESR968 - Jul 13, 06:01 UTCJul 13, 06:40 UTC40m
2026-07-13 ESR967 - Jul 13, 03:45 UTCJul 13, 04:25 UTC40m
2026-07-13 ESR902 - Jul 13, 02:05 UTCJul 13, 02:25 UTC20m
2026-07-12 ESR711 - Jul 12, 23:00 UTCJul 12, 23:30 UTC30m
2026-07-12 ESR782 - Jul 12, 19:20 UTCJul 12, 21:15 UTC1h 55m
2026-07-12 ESR781 - Jul 12, 15:45 UTCJul 12, 17:45 UTC2h 0m
2026-07-12 ESR716 - Jul 12, 14:05 UTCJul 12, 14:30 UTC25m
2026-07-12 ESR233 - Jul 12, 12:10 UTCJul 12, 12:40 UTC30m
2026-07-12 ESR224 - Jul 12, 10:30 UTCJul 12, 11:05 UTC35m
2026-07-12 ESR223 - Jul 12, 07:50 UTCJul 12, 08:35 UTC45m
2026-07-12 ESR216 - Jul 12, 05:45 UTCJul 12, 06:25 UTC40m
2026-07-12 ESR213 - Jul 12, 03:10 UTCJul 12, 03:55 UTC45m
2026-07-12 ESR271F - Jul 12, 01:15 UTCJul 12, 01:40 UTC25m
2026-07-11 ESR716 - Jul 11, 14:20 UTCJul 11, 14:50 UTC30m
2026-07-11 ESR233 - Jul 11, 12:20 UTCJul 11, 12:55 UTC35m
2026-07-11 ESR224 - Jul 11, 10:45 UTCJul 11, 11:25 UTC40m
2026-07-11 ESR223 - Jul 11, 07:15 UTCJul 11, 07:50 UTC35m
2026-07-11 ESR216 - Jul 11, 05:40 UTCJul 11, 06:15 UTC35m
2026-07-11 ESR213 - Jul 11, 02:55 UTCJul 11, 03:40 UTC45m
2026-07-11 ESR208 - Jul 11, 01:05 UTCJul 11, 01:50 UTC45m
2026-07-10 ESR207 - Jul 10, 22:45 UTCJul 10, 23:20 UTC35m
2026-07-10 ESR278 - Jul 10, 12:55 UTCJul 10, 13:35 UTC40m
2026-07-10 ESR277 - Jul 10, 10:35 UTCJul 10, 11:10 UTC35m
2026-07-10 ESR276 - Jul 10, 08:45 UTCJul 10, 09:30 UTC45m
2026-07-10 ESR275 - Jul 10, 06:40 UTCJul 10, 07:15 UTC35m
2026-07-10 ESR274 - Jul 10, 05:00 UTCJul 10, 05:45 UTC45m
2026-07-10 ESR273 - Jul 10, 02:50 UTCJul 10, 03:25 UTC35m
2026-07-10 ESR272 - Jul 10, 01:05 UTCJul 10, 01:45 UTC40m
2026-07-09 ESR711 - Jul 9, 22:55 UTCJul 9, 23:25 UTC30m
2026-07-09 ESR782 - Jul 9, 20:30 UTCJul 9, 21:00 UTC30m
2026-07-09 ESR782 - Jul 9, 19:00 UTCJul 9, 19:15 UTC15m
2026-07-09 ESR781 - Jul 9, 17:00 UTCJul 9, 17:15 UTC15m
2026-07-09 ESR781 - Jul 9, 15:15 UTCJul 9, 15:55 UTC40m
2026-07-09 ESR716 - Jul 9, 13:25 UTCJul 9, 13:50 UTC25m
2026-07-09 ESR233 - Jul 9, 11:10 UTCJul 9, 11:45 UTC35m
2026-07-09 ESR224 - Jul 9, 09:15 UTCJul 9, 09:55 UTC40m
2026-07-09 ESR223 - Jul 9, 07:10 UTCJul 9, 07:45 UTC35m
2026-07-09 ESR216 - Jul 9, 05:25 UTCJul 9, 06:05 UTC40m
2026-07-09 ESR213 - Jul 9, 03:05 UTCJul 9, 03:55 UTC50m
2026-07-09 ESR272 - Jul 9, 01:05 UTCJul 9, 01:50 UTC45m
2026-07-08 ESR205 - Jul 8, 22:05 UTCJul 8, 22:50 UTC45m
2026-07-08 ESR232 - Jul 8, 13:10 UTCJul 8, 13:45 UTC35m
2026-07-08 ESR231 - Jul 8, 11:15 UTCJul 8, 11:50 UTC35m

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 HL8544 page for operator, model, and routing details .

Mode-S 71C544 frequently asked

What is Mode-S code 71C544?
71C544 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8544.
Where is Mode-S 71C544 registered?
Mode-S code 71C544 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 71C544 broadcasting right now?
No active broadcast right now. Last signal was 1h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C544, octal 34342504, decimal 7,456,068.
What flights does 71C544 operate?
Mode-S 71C544 has broadcast 20 distinct callsigns, including ESR782, ESR781, ESR233, ESR716, ESR711.