sensors Mode-S transponder

71BF57

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

Currently assigned to HL7757 · BOEING 737-800

Hex
71BF57
Octal
34337527
Decimal
7,454,551
Country
KR
Tail
HL7757
Type
B738
No current signal · last broadcast 14h ago
Flights observed
13
Distinct callsigns
7
Country
KR
Last broadcast
14h ago

Last known position

Most recent position reported by Mode-S 71BF57.

Country allocation

The ICAO 24-bit address 71BF57 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 7 distinct

Callsign Airline Flights Last seen
JNA131 Jin Air 3 2026-04-13
JNA263 - 2 2026-04-13
JNA238 - 2 2026-04-14
JNA237 Jin Air 2 2026-04-14
JNA132 - 2 2026-04-13
JNA264 - 1 2026-04-13
JNA262 - 1 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-14 JNA238 - Apr 14, 09:10 UTCApr 14, 10:10 UTC1h 0m
2026-04-14 JNA238 - Apr 14, 08:55 UTCApr 14, 09:05 UTC10m
2026-04-14 JNA237 ICN → KIX Apr 14, 07:15 UTCApr 14, 07:35 UTC20m
2026-04-14 JNA237 ICN → KIX Apr 14, 06:15 UTCApr 14, 07:05 UTC50m
2026-04-13 JNA132 - Apr 13, 19:55 UTCApr 13, 21:50 UTC1h 55m
2026-04-13 JNA132 - Apr 13, 16:50 UTCApr 13, 20:10 UTC3h 20m
2026-04-13 JNA131 ICN → BKI Apr 13, 12:20 UTCApr 13, 15:30 UTC3h 10m
2026-04-13 JNA131 ICN → BKI Apr 13, 12:00 UTCApr 13, 15:30 UTC3h 30m
2026-04-13 JNA131 ICN → BKI Apr 13, 10:45 UTCApr 13, 12:15 UTC1h 30m
2026-04-13 JNA264 - Apr 13, 06:00 UTCApr 13, 06:50 UTC50m
2026-04-13 JNA263 - Apr 13, 03:55 UTCApr 13, 04:05 UTC10m
2026-04-13 JNA263 - Apr 13, 03:35 UTCApr 13, 04:05 UTC30m
2026-04-13 JNA262 - Apr 13, 01:00 UTCApr 13, 01:55 UTC55m

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 HL7757 page for operator, model, and routing details .

Mode-S 71BF57 frequently asked

What is Mode-S code 71BF57?
71BF57 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL7757.
Where is Mode-S 71BF57 registered?
Mode-S code 71BF57 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 71BF57 broadcasting right now?
No active broadcast right now. Last signal was 14h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71BF57, octal 34337527, decimal 7,454,551.
What flights does 71BF57 operate?
Mode-S 71BF57 has broadcast 7 distinct callsigns, including JNA131, JNA263, JNA238, JNA237, JNA132.