Apparatus

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sensors Mode-S transponder

71C539

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

Currently assigned to HL8539 · BOEING 737-800

Hex
71C539
Octal
34342471
Decimal
7,456,057
Country
KR
Tail
HL8539
Type
B738
No current signal · last broadcast Jul 26, 21:35 UTC
Flights observed
562
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 21:35 UTC

Last known position

Most recent position reported by Mode-S 71C539.

Country allocation

The ICAO 24-bit address 71C539 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
JJA1101 Jeju Air 9 2026-05-22
JJA1616 Jeju Air 7 2026-05-22
JJA1615 Jeju Air 7 2026-05-22
JJA1504 Jeju Air 7 2026-05-18
JJA1503 Jeju Air 7 2026-05-18
JJA1408 Jeju Air 7 2026-05-20
JJA1407 Jeju Air 7 2026-05-20
JJA1402 Jeju Air 7 2026-05-20
JJA1401 Jeju Air 7 2026-05-19
JJA1328 - 7 2026-07-10
JJA1327 - 7 2026-07-10
JJA1326 - 7 2026-07-10
JJA1325 - 7 2026-07-09
JJA118 Jeju Air 7 2026-07-23
JJA113 Jeju Air 7 2026-07-23
JJA6256 - 6 2026-07-18
JJA2126 - 6 2026-05-14
JJA126 - 6 2026-07-14
JJA125 - 6 2026-07-14
JJA1102 Jeju Air 6 2026-05-23

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 JJA2158 - Jul 26, 20:45 UTCJul 26, 21:30 UTC45m
2026-07-26 JJA2158 - Jul 26, 11:50 UTCJul 26, 19:35 UTC7h 45m
2026-07-26 JJA512 CJU → PUS Jul 26, 10:05 UTCJul 26, 10:20 UTC15m
2026-07-26 JJA513 PUS → CJU Jul 26, 08:10 UTCJul 26, 08:25 UTC15m
2026-07-26 JJA510 CJU → PUS Jul 26, 06:50 UTCJul 26, 07:15 UTC25m
2026-07-26 JJA123 GMP → CJU Jul 26, 04:35 UTCJul 26, 05:10 UTC35m
2026-07-26 JJA114 CJU → GMP Jul 26, 02:55 UTCJul 26, 03:35 UTC40m
2026-07-26 JJA301 KWJ → CJU Jul 26, 00:50 UTCJul 26, 01:00 UTC10m
2026-07-25 JJA302 CJU → KWJ Jul 25, 23:40 UTCJul 25, 23:55 UTC15m
2026-07-25 JJA103 GMP → CJU Jul 25, 21:35 UTCJul 25, 22:05 UTC30m
2026-07-25 JJA138 CJU → GMP Jul 25, 12:40 UTCJul 25, 13:20 UTC40m
2026-07-25 JJA227 CJJ → CJU Jul 25, 10:40 UTCJul 25, 11:05 UTC25m
2026-07-25 JJA228 CJU → CJJ Jul 25, 09:00 UTCJul 25, 09:30 UTC30m
2026-07-25 JJA509 PUS → CJU Jul 25, 07:05 UTCJul 25, 07:20 UTC15m
2026-07-25 JJA508 CJU → PUS Jul 25, 05:35 UTCJul 25, 05:55 UTC20m
2026-07-25 JJA505 PUS → CJU Jul 25, 03:30 UTCJul 25, 03:45 UTC15m
2026-07-25 JJA504 CJU → PUS Jul 25, 02:10 UTCJul 25, 02:30 UTC20m
2026-07-25 JJA109 GMP → CJU Jul 25, 00:05 UTCJul 25, 00:40 UTC35m
2026-07-24 JJA904 PUS → GMP Jul 24, 22:25 UTCJul 24, 23:05 UTC40m
2026-07-24 JJA512 CJU → PUS Jul 24, 10:10 UTCJul 24, 10:30 UTC20m
2026-07-24 JJA513 PUS → CJU Jul 24, 08:15 UTCJul 24, 08:35 UTC20m
2026-07-24 JJA510 CJU → PUS Jul 24, 07:05 UTCJul 24, 07:25 UTC20m
2026-07-24 JJA123 GMP → CJU Jul 24, 04:45 UTCJul 24, 05:20 UTC35m
2026-07-24 JJA114 CJU → GMP Jul 24, 03:05 UTCJul 24, 03:45 UTC40m
2026-07-24 JJA301 KWJ → CJU Jul 24, 01:05 UTCJul 24, 01:15 UTC10m
2026-07-23 JJA302 CJU → KWJ Jul 23, 23:35 UTCJul 23, 23:50 UTC15m
2026-07-23 JJA103 GMP → CJU Jul 23, 21:35 UTCJul 23, 22:10 UTC35m
2026-07-23 JJA136 - Jul 23, 12:25 UTCJul 23, 13:05 UTC40m
2026-07-23 JJA225 CJJ → CJU Jul 23, 10:05 UTCJul 23, 10:35 UTC30m
2026-07-23 JJA226 CJU → CJJ Jul 23, 08:35 UTCJul 23, 09:05 UTC30m
2026-07-23 JJA127 GMP → CJU Jul 23, 06:20 UTCJul 23, 06:50 UTC30m
2026-07-23 JJA118 CJU → GMP Jul 23, 04:05 UTCJul 23, 04:45 UTC40m
2026-07-23 JJA113 GMP → CJU Jul 23, 01:55 UTCJul 23, 02:30 UTC35m
2026-07-23 JJA104 CJU → GMP Jul 23, 00:15 UTCJul 23, 00:55 UTC40m
2026-07-22 JJA105 GMP → CJU Jul 22, 22:05 UTCJul 22, 22:45 UTC40m
2026-07-22 JJA136 - Jul 22, 12:25 UTCJul 22, 13:05 UTC40m
2026-07-22 JJA118 CJU → GMP Jul 22, 04:05 UTCJul 22, 04:45 UTC40m
2026-07-22 JJA113 GMP → CJU Jul 22, 02:00 UTCJul 22, 02:40 UTC40m
2026-07-22 JJA104 CJU → GMP Jul 22, 00:20 UTCJul 22, 01:00 UTC40m
2026-07-21 JJA105 GMP → CJU Jul 21, 22:15 UTCJul 21, 22:50 UTC35m
2026-07-21 JJA128 CJU → GMP Jul 21, 09:40 UTCJul 21, 10:25 UTC45m
2026-07-21 JJA129 GMP → CJU Jul 21, 07:30 UTCJul 21, 08:10 UTC40m
2026-07-21 JJA122 CJU → GMP Jul 21, 05:35 UTCJul 21, 06:15 UTC40m
2026-07-21 JJA117 GMP → CJU Jul 21, 03:30 UTCJul 21, 04:05 UTC35m
2026-07-21 JJA108 CJU → GMP Jul 21, 01:35 UTCJul 21, 02:35 UTC1h 0m
2026-07-20 JJA711 TAE → CJU Jul 20, 23:20 UTCJul 20, 23:35 UTC15m
2026-07-20 JJA706 - Jul 20, 09:35 UTCJul 20, 10:05 UTC30m
2026-07-20 JJA131 GMP → CJU Jul 20, 07:25 UTCJul 20, 07:55 UTC30m
2026-07-20 JJA120 CJU → GMP Jul 20, 05:25 UTCJul 20, 06:05 UTC40m
2026-07-20 JJA115 GMP → CJU Jul 20, 03:05 UTCJul 20, 03:40 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 HL8539 page for operator, model, and routing details .

Mode-S 71C539 frequently asked

What is Mode-S code 71C539?
71C539 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8539.
Where is Mode-S 71C539 registered?
Mode-S code 71C539 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 71C539 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 71C539, octal 34342471, decimal 7,456,057.
What flights does 71C539 operate?
Mode-S 71C539 has broadcast 20 distinct callsigns, including JJA1101, JJA1616, JJA1615, JJA1504, JJA1503.