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 2h ago
Flights observed
477
Distinct callsigns
20
Country
KR
Last broadcast
2h ago

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
JJA2126 - 6 2026-05-14
JJA125 - 6 2026-07-14
JJA1102 Jeju Air 6 2026-05-23
JJA107 - 6 2026-07-10
JJA2315 Jeju Air 5 2026-05-05
JJA214 - 5 2026-07-11
JJA213 - 5 2026-07-11

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 JJA125 - Jul 14, 05:45 UTCJul 14, 06:25 UTC40m
2026-07-14 JJA154 - Jul 14, 03:40 UTCJul 14, 04:20 UTC40m
2026-07-14 JJA153 - Jul 14, 01:20 UTCJul 14, 01:55 UTC35m
2026-07-13 JJA152 - Jul 13, 23:35 UTCJul 14, 00:20 UTC45m
2026-07-13 JJA151 - Jul 13, 21:30 UTCJul 13, 22:05 UTC35m
2026-07-13 JJA134 - Jul 13, 12:20 UTCJul 13, 13:05 UTC45m
2026-07-13 JJA135 - Jul 13, 10:05 UTCJul 13, 10:40 UTC35m
2026-07-13 JJA126 - Jul 13, 08:25 UTCJul 13, 09:05 UTC40m
2026-07-13 JJA125 - Jul 13, 06:10 UTCJul 13, 06:55 UTC45m
2026-07-13 JJA154 - Jul 13, 03:45 UTCJul 13, 04:25 UTC40m
2026-07-13 JJA153 - Jul 13, 01:25 UTCJul 13, 02:01 UTC35m
2026-07-12 JJA152 - Jul 12, 23:40 UTCJul 13, 00:20 UTC40m
2026-07-12 JJA151 - Jul 12, 21:35 UTCJul 12, 22:10 UTC35m
2026-07-12 JJA134 - Jul 12, 12:50 UTCJul 12, 13:25 UTC35m
2026-07-12 JJA225 - Jul 12, 10:45 UTCJul 12, 11:15 UTC30m
2026-07-12 JJA226 - Jul 12, 09:10 UTCJul 12, 09:40 UTC30m
2026-07-12 JJA127 - Jul 12, 06:40 UTCJul 12, 07:20 UTC40m
2026-07-12 JJA118 - Jul 12, 05:01 UTCJul 12, 05:40 UTC40m
2026-07-12 JJA113 - Jul 12, 02:40 UTCJul 12, 03:25 UTC45m
2026-07-11 JJA094F ICN → GMP Jul 11, 21:15 UTCJul 11, 21:30 UTC15m
2026-07-11 JJA194 CJU → GMP Jul 11, 14:00 UTCJul 11, 14:35 UTC35m
2026-07-11 JJA227 - Jul 11, 11:35 UTCJul 11, 12:05 UTC30m
2026-07-11 JJA228 - Jul 11, 10:00 UTCJul 11, 10:30 UTC30m
2026-07-11 JJA509 - Jul 11, 06:55 UTCJul 11, 07:15 UTC20m
2026-07-11 JJA506 - Jul 11, 05:01 UTCJul 11, 05:31 UTC30m
2026-07-11 JJA213 - Jul 11, 02:40 UTCJul 11, 03:10 UTC30m
2026-07-11 JJA214 - Jul 11, 01:10 UTCJul 11, 01:40 UTC30m
2026-07-10 JJA107 - Jul 10, 22:50 UTCJul 10, 23:25 UTC35m
2026-07-10 JJA140 - Jul 10, 12:40 UTCJul 10, 13:20 UTC40m
2026-07-10 JJA137 - Jul 10, 10:30 UTCJul 10, 11:05 UTC35m
2026-07-10 JJA1328 KIX → GMP Jul 10, 07:45 UTCJul 10, 09:10 UTC1h 25m
2026-07-10 JJA1327 GMP → KIX Jul 10, 05:05 UTCJul 10, 06:25 UTC1h 20m
2026-07-10 JJA1326 - Jul 10, 02:10 UTCJul 10, 03:35 UTC1h 25m
2026-07-09 JJA1325 GMP → KIX Jul 9, 23:30 UTCJul 10, 00:55 UTC1h 25m
2026-07-09 JJA142 - Jul 9, 13:05 UTCJul 9, 13:50 UTC45m
2026-07-09 JJA139 - Jul 9, 10:50 UTCJul 9, 11:40 UTC50m
2026-07-09 JJA1328 KIX → GMP Jul 9, 07:55 UTCJul 9, 09:15 UTC1h 20m
2026-07-09 JJA1327 GMP → KIX Jul 9, 05:10 UTCJul 9, 06:35 UTC1h 25m
2026-07-09 JJA1326 KIX → GMP Jul 9, 02:05 UTCJul 9, 03:30 UTC1h 25m
2026-07-08 JJA1325 GMP → KIX Jul 8, 23:20 UTCJul 9, 00:40 UTC1h 20m
2026-07-08 JJA158 - Jul 8, 11:30 UTCJul 8, 12:10 UTC40m
2026-07-08 JJA157 - Jul 8, 09:20 UTCJul 8, 09:55 UTC35m
2026-07-08 JJA156 - Jul 8, 07:40 UTCJul 8, 08:25 UTC45m
2026-07-08 JJA155 - Jul 8, 05:30 UTCJul 8, 06:05 UTC35m
2026-07-08 JJA154 - Jul 8, 03:35 UTCJul 8, 04:15 UTC40m
2026-07-08 JJA153 - Jul 8, 01:30 UTCJul 8, 02:05 UTC35m
2026-07-07 JJA152 - Jul 7, 23:45 UTCJul 8, 00:25 UTC40m
2026-07-07 JJA151 - Jul 7, 21:45 UTCJul 7, 22:20 UTC35m
2026-07-07 JJA130 - Jul 7, 09:20 UTCJul 7, 09:55 UTC35m
2026-07-07 JJA705 - Jul 7, 07:30 UTCJul 7, 07:50 UTC20m

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 2h ago.
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.