Apparatus

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sensors Mode-S transponder

71C541

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

Currently assigned to HL8541 · BOEING 737 MAX 8

Hex
71C541
Octal
34342501
Decimal
7,456,065
Country
KR
Tail
HL8541
Type
B38M
Broadcasting now · callsign ESR610 · 36,000 ft
Flights observed
544
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 21:55 UTC

Current position

71C541 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 71C541 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
ESR632 Eastar Jet 19 2026-05-14
ESR631 Eastar Jet 18 2026-05-14
ESR951 - 16 2026-07-10
ESR918 Eastar Jet 15 2026-07-23
ESR861 Eastar Jet 15 2026-05-14
ESR952 - 14 2026-07-10
ESR917 Eastar Jet 13 2026-07-23
ESR913 Eastar Jet 13 2026-07-19
ESR536 Eastar Jet 12 2026-05-16
ESR271 Eastar Jet 12 2026-07-25
ESR219 Eastar Jet 12 2026-07-25
ESR212 Eastar Jet 12 2026-07-25
ESR211 Eastar Jet 12 2026-07-25
ESR915 Eastar Jet 11 2026-07-23
ESR284 Eastar Jet 11 2026-07-25
ESR206 Eastar Jet 11 2026-07-25
ESR914 Eastar Jet 10 2026-07-19
ESR862 Eastar Jet 10 2026-05-14
ESR967 Eastar Jet 9 2026-07-22
ESR916 Eastar Jet 9 2026-07-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ESR201 GMP → CJU Jul 26, 21:20 UTCJul 26, 21:55 UTC35m
2026-07-26 ESR278 CJU → GMP Jul 26, 12:40 UTCJul 26, 13:20 UTC40m
2026-07-26 ESR277 GMP → CJU Jul 26, 10:40 UTCJul 26, 11:10 UTC30m
2026-07-26 ESR276 CJU → GMP Jul 26, 09:05 UTCJul 26, 09:40 UTC35m
2026-07-26 ESR275 GMP → CJU Jul 26, 06:50 UTCJul 26, 07:25 UTC35m
2026-07-26 ESR274 CJU → GMP Jul 26, 05:05 UTCJul 26, 05:50 UTC45m
2026-07-26 ESR273 GMP → CJU Jul 26, 02:55 UTCJul 26, 03:30 UTC35m
2026-07-26 ESR272 CJU → GMP Jul 26, 01:10 UTCJul 26, 01:50 UTC40m
2026-07-25 ESR271 GMP → CJU Jul 25, 23:05 UTCJul 25, 23:35 UTC30m
2026-07-25 ESR230 CJU → GMP Jul 25, 12:25 UTCJul 25, 13:05 UTC40m
2026-07-25 ESR283 GMP → CJU Jul 25, 10:20 UTCJul 25, 10:55 UTC35m
2026-07-25 ESR284 CJU → GMP Jul 25, 08:30 UTCJul 25, 09:15 UTC45m
2026-07-25 ESR219 GMP → CJU Jul 25, 06:15 UTCJul 25, 06:50 UTC35m
2026-07-25 ESR212 CJU → GMP Jul 25, 04:25 UTCJul 25, 05:05 UTC40m
2026-07-25 ESR211 GMP → CJU Jul 25, 02:15 UTCJul 25, 02:45 UTC30m
2026-07-25 ESR206 CJU → GMP Jul 25, 00:20 UTCJul 25, 01:05 UTC45m
2026-07-24 ESR205 GMP → CJU Jul 24, 22:10 UTCJul 24, 22:50 UTC40m
2026-07-24 ESR278 - Jul 24, 13:00 UTCJul 24, 13:40 UTC40m
2026-07-24 ESR277 GMP → CJU Jul 24, 10:45 UTCJul 24, 11:20 UTC35m
2026-07-24 ESR222 CJU → GMP Jul 24, 09:00 UTCJul 24, 09:40 UTC40m
2026-07-24 ESR221 GMP → CJU Jul 24, 06:50 UTCJul 24, 07:20 UTC30m
2026-07-24 ESR214 CJU → GMP Jul 24, 05:00 UTCJul 24, 05:40 UTC40m
2026-07-24 ESR281 GMP → CJU Jul 24, 02:50 UTCJul 24, 03:25 UTC35m
2026-07-24 ESR282 CJU → GMP Jul 24, 00:55 UTCJul 24, 01:35 UTC40m
2026-07-23 ESR901 PUS → CJU Jul 23, 22:30 UTCJul 23, 22:45 UTC15m
2026-07-23 ESR918 CNX → PUS Jul 23, 20:45 UTCJul 23, 21:20 UTC35m
2026-07-23 ESR918 CNX → PUS Jul 23, 16:20 UTCJul 23, 17:40 UTC1h 20m
2026-07-23 ESR917 PUS → CNX Jul 23, 10:10 UTCJul 23, 14:45 UTC4h 35m
2026-07-23 ESR916 KIX → PUS Jul 23, 07:15 UTCJul 23, 08:25 UTC1h 10m
2026-07-23 ESR915 PUS → KIX Jul 23, 04:40 UTCJul 23, 05:45 UTC1h 5m
2026-07-23 ESR942 FUK → PUS Jul 23, 02:10 UTCJul 23, 02:50 UTC40m
2026-07-23 ESR941 PUS → FUK Jul 23, 00:35 UTCJul 23, 00:50 UTC15m
2026-07-22 ESR982 PQC → PUS Jul 22, 21:00 UTCJul 22, 21:40 UTC40m
2026-07-22 ESR981 - Jul 22, 11:10 UTCJul 22, 19:55 UTC8h 45m
2026-07-22 ESR967 PUS → KMJ Jul 22, 04:05 UTCJul 22, 04:35 UTC30m
2026-07-22 ESR902 - Jul 22, 01:30 UTCJul 22, 01:45 UTC15m
2026-07-21 ESR271 GMP → CJU Jul 21, 22:55 UTCJul 21, 23:35 UTC40m
2026-07-21 ESR230 CJU → GMP Jul 21, 12:15 UTCJul 21, 12:55 UTC40m
2026-07-21 ESR283 GMP → CJU Jul 21, 10:15 UTCJul 21, 10:45 UTC30m
2026-07-21 ESR284 CJU → GMP Jul 21, 08:25 UTCJul 21, 09:10 UTC45m
2026-07-21 ESR219 GMP → CJU Jul 21, 06:05 UTCJul 21, 06:40 UTC35m
2026-07-21 ESR212 CJU → GMP Jul 21, 04:15 UTCJul 21, 05:05 UTC50m
2026-07-21 ESR211 GMP → CJU Jul 21, 02:15 UTCJul 21, 02:50 UTC35m
2026-07-21 ESR206 CJU → GMP Jul 21, 00:20 UTCJul 21, 01:00 UTC40m
2026-07-20 ESR205 GMP → CJU Jul 20, 22:10 UTCJul 20, 22:40 UTC30m
2026-07-20 ESR230 CJU → GMP Jul 20, 13:30 UTCJul 20, 14:00 UTC30m
2026-07-20 ESR283 GMP → CJU Jul 20, 11:15 UTCJul 20, 11:50 UTC35m
2026-07-20 ESR284 - Jul 20, 09:30 UTCJul 20, 10:10 UTC40m
2026-07-20 ESR219 GMP → CJU Jul 20, 07:15 UTCJul 20, 07:50 UTC35m
2026-07-20 ESR212 CJU → GMP Jul 20, 05:10 UTCJul 20, 05:55 UTC45m

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 HL8541 page for operator, model, and routing details .

Mode-S 71C541 frequently asked

What is Mode-S code 71C541?
71C541 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8541.
Where is Mode-S 71C541 registered?
Mode-S code 71C541 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 71C541 broadcasting right now?
Yes. Mode-S 71C541 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C541, octal 34342501, decimal 7,456,065.
What flights does 71C541 operate?
Mode-S 71C541 has broadcast 20 distinct callsigns, including ESR632, ESR631, ESR951, ESR918, ESR861.