sensors Mode-S transponder

71BF40

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

Currently assigned to HL7740 · AIRBUS A-330-300

Hex
71BF40
Octal
34337500
Decimal
7,454,528
Country
KR
Tail
HL7740
Type
A333
No current signal · last broadcast 2h ago
Flights observed
8
Distinct callsigns
8
Country
KR
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 71BF40.

Country allocation

The ICAO 24-bit address 71BF40 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 8 distinct

Callsign Airline Flights Last seen
AAR831B - 1 2026-05-18
AAR370 Asiana Airlines 1 2026-05-19
AAR369 Asiana Airlines 1 2026-05-19
AAR360 Asiana Airlines 1 2026-05-20
AAR178 Asiana Airlines 1 2026-05-20
AAR177 Asiana Airlines 1 2026-05-20
AAR108 Asiana Airlines 1 2026-05-19
AAR107 Asiana Airlines 1 2026-05-20

Recent flights last 8

DateFlightRouteTakeoffLandingDuration
2026-05-20 AAR177 HND → ICN May 20, 16:50 UTCMay 20, 18:00 UTC1h 10m
2026-05-20 AAR178 ICN → HND May 20, 12:40 UTCMay 20, 14:25 UTC1h 45m
2026-05-20 AAR360 HGH → ICN May 20, 04:05 UTCMay 20, 09:15 UTC5h 11m
2026-05-20 AAR107 NRT → ICN May 20, 00:15 UTCMay 20, 02:30 UTC2h 15m
2026-05-19 AAR108 ICN → NRT May 19, 09:50 UTCMay 19, 11:45 UTC1h 55m
2026-05-19 AAR370 CAN → ICN May 19, 07:20 UTCMay 19, 07:50 UTC30m
2026-05-19 AAR369 ICN → CAN May 19, 00:00 UTCMay 19, 00:25 UTC25m
2026-05-18 AAR831B - May 18, 04:40 UTCMay 18, 05:50 UTC1h 10m

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 HL7740 page for operator, model, and routing details .

Mode-S 71BF40 frequently asked

What is Mode-S code 71BF40?
71BF40 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL7740.
Where is Mode-S 71BF40 registered?
Mode-S code 71BF40 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 71BF40 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 71BF40, octal 34337500, decimal 7,454,528.
What flights does 71BF40 operate?
Mode-S 71BF40 has broadcast 8 distinct callsigns, including AAR831B, AAR370, AAR369, AAR360, AAR178.