Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

71C504

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

Currently assigned to HL8504 · AIRBUS A-321neo

Hex
71C504
Octal
34342404
Decimal
7,456,004
Country
KR
Tail
HL8504
Type
A21N
No current signal · last broadcast Jul 26, 23:00 UTC
Flights observed
435
Distinct callsigns
18
Country
KR
Last broadcast
Jul 26, 23:00 UTC

Last known position

Most recent position reported by Mode-S 71C504.

Country allocation

The ICAO 24-bit address 71C504 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 18 distinct

Callsign Airline Flights Last seen
ABL156 Air Busan 56 2026-07-26
ABL173 Air Busan 54 2026-07-25
ABL174 Air Busan 53 2026-07-25
ABL155 Air Busan 52 2026-07-25
ABL157 Air Busan 50 2026-07-26
ABL158 Air Busan 49 2026-07-26
ABL787 Air Busan 35 2026-07-26
ABL788 - 29 2026-07-16
ABL7475 Air Busan 24 2026-07-25
ABL7485 Air Busan 23 2026-07-25
ABL3945 Air Busan 2 2026-04-26
ABL3935 Air Busan 2 2026-04-26
ABL804F - 1 2026-07-13
ABL803F - 1 2026-07-13
ABL712 - 1 2026-07-13
ABL711 - 1 2026-07-13
ABL172 - 1 2026-07-16
ABL171 - 1 2026-07-16

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 ABL156 ICN → FUK Jul 26, 22:35 UTCJul 26, 23:00 UTC25m
2026-07-26 ABL787 ICN → CXR Jul 26, 08:50 UTCJul 26, 20:05 UTC11h 15m
2026-07-26 ABL157 FUK → ICN Jul 26, 05:30 UTCJul 26, 06:30 UTC1h 0m
2026-07-26 ABL158 ICN → FUK Jul 26, 02:50 UTCJul 26, 03:45 UTC55m
2026-07-25 ABL7485 CNX → ICN Jul 25, 17:55 UTCJul 25, 22:55 UTC5h 0m
2026-07-25 ABL7475 ICN → CNX Jul 25, 11:20 UTCJul 25, 16:05 UTC4h 45m
2026-07-25 ABL173 KIX → ICN Jul 25, 07:25 UTCJul 25, 08:55 UTC1h 30m
2026-07-25 ABL174 ICN → KIX Jul 25, 04:20 UTCJul 25, 05:45 UTC1h 25m
2026-07-25 ABL155 FUK → ICN Jul 25, 01:10 UTCJul 25, 02:20 UTC1h 10m
2026-07-24 ABL156 ICN → FUK Jul 24, 22:40 UTCJul 24, 23:20 UTC40m
2026-07-24 ABL173 KIX → ICN Jul 24, 07:30 UTCJul 24, 08:55 UTC1h 25m
2026-07-24 ABL174 ICN → KIX Jul 24, 04:10 UTCJul 24, 05:40 UTC1h 30m
2026-07-24 ABL155 FUK → ICN Jul 24, 01:25 UTCJul 24, 02:20 UTC55m
2026-07-23 ABL156 ICN → FUK Jul 23, 22:40 UTCJul 23, 23:25 UTC45m
2026-07-23 ABL787 ICN → CXR Jul 23, 08:30 UTCJul 23, 19:25 UTC10h 55m
2026-07-23 ABL157 FUK → ICN Jul 23, 05:20 UTCJul 23, 06:20 UTC1h 0m
2026-07-23 ABL158 ICN → FUK Jul 23, 02:55 UTCJul 23, 03:55 UTC1h 0m
2026-07-22 ABL7485 - Jul 22, 17:45 UTCJul 22, 22:55 UTC5h 10m
2026-07-22 ABL7475 ICN → CNX Jul 22, 11:20 UTCJul 22, 16:20 UTC5h 0m
2026-07-22 ABL174 ICN → KIX Jul 22, 04:15 UTCJul 22, 05:25 UTC1h 10m
2026-07-22 ABL155 FUK → ICN Jul 22, 01:15 UTCJul 22, 02:25 UTC1h 10m
2026-07-21 ABL156 ICN → FUK Jul 21, 22:40 UTCJul 21, 23:30 UTC50m
2026-07-21 ABL787 ICN → CXR Jul 21, 08:25 UTCJul 21, 19:35 UTC11h 10m
2026-07-21 ABL157 FUK → ICN Jul 21, 05:20 UTCJul 21, 06:20 UTC1h 0m
2026-07-21 ABL158 ICN → FUK Jul 21, 02:55 UTCJul 21, 03:45 UTC50m
2026-07-20 ABL173 KIX → ICN Jul 20, 07:30 UTCJul 20, 08:55 UTC1h 25m
2026-07-20 ABL174 ICN → KIX Jul 20, 04:15 UTCJul 20, 05:55 UTC1h 40m
2026-07-20 ABL155 FUK → ICN Jul 20, 01:20 UTCJul 20, 02:25 UTC1h 5m
2026-07-19 ABL156 ICN → FUK Jul 19, 22:45 UTCJul 19, 23:45 UTC1h 0m
2026-07-19 ABL787 ICN → CXR Jul 19, 08:50 UTCJul 19, 19:20 UTC10h 30m
2026-07-19 ABL157 - Jul 19, 05:20 UTCJul 19, 06:10 UTC50m
2026-07-19 ABL158 ICN → FUK Jul 19, 02:45 UTCJul 19, 03:30 UTC45m
2026-07-18 ABL7485 - Jul 18, 18:00 UTCJul 18, 22:50 UTC4h 50m
2026-07-18 ABL7475 ICN → CNX Jul 18, 11:30 UTCJul 18, 16:05 UTC4h 35m
2026-07-18 ABL173 KIX → ICN Jul 18, 07:25 UTCJul 18, 08:45 UTC1h 20m
2026-07-18 ABL174 ICN → KIX Jul 18, 04:20 UTCJul 18, 05:50 UTC1h 30m
2026-07-18 ABL155 - Jul 18, 01:10 UTCJul 18, 02:05 UTC55m
2026-07-17 ABL156 ICN → FUK Jul 17, 22:40 UTCJul 17, 23:30 UTC50m
2026-07-17 ABL173 KIX → ICN Jul 17, 07:25 UTCJul 17, 08:40 UTC1h 15m
2026-07-17 ABL174 ICN → KIX Jul 17, 04:14 UTCJul 17, 05:39 UTC1h 25m
2026-07-17 ABL155 - Jul 17, 01:15 UTCJul 17, 02:10 UTC55m
2026-07-16 ABL156 ICN → FUK Jul 16, 22:45 UTCJul 16, 23:29 UTC45m
2026-07-16 ABL788 ICN → ICN Jul 16, 08:50 UTCJul 16, 19:40 UTC10h 50m
2026-07-16 ABL171 - Jul 16, 04:15 UTCJul 16, 05:40 UTC1h 25m
2026-07-16 ABL172 - Jul 16, 01:00 UTCJul 16, 02:25 UTC1h 25m
2026-07-15 ABL7485 - Jul 15, 17:50 UTCJul 15, 22:55 UTC5h 5m
2026-07-15 ABL7475 ICN → CNX Jul 15, 11:20 UTCJul 15, 16:00 UTC4h 40m
2026-07-15 ABL173 KIX → ICN Jul 15, 07:20 UTCJul 15, 08:40 UTC1h 20m
2026-07-15 ABL174 ICN → KIX Jul 15, 04:15 UTCJul 15, 05:35 UTC1h 20m
2026-07-15 ABL155 - Jul 15, 01:15 UTCJul 15, 02:10 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 HL8504 page for operator, model, and routing details .

Mode-S 71C504 frequently asked

What is Mode-S code 71C504?
71C504 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8504.
Where is Mode-S 71C504 registered?
Mode-S code 71C504 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 71C504 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 23:00 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C504, octal 34342404, decimal 7,456,004.
What flights does 71C504 operate?
Mode-S 71C504 has broadcast 18 distinct callsigns, including ABL156, ABL173, ABL174, ABL155, ABL157.