sensors Mode-S transponder

71C717

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

Currently assigned to HL8717 · BOEING 737 MAX 8

Hex
71C717
Octal
34343427
Decimal
7,456,535
Country
KR
Tail
HL8717
Type
B38M
Broadcasting now · callsign ESR602 · 35,975 ft
Flights observed
12
Distinct callsigns
6
Country
KR
Last broadcast
17h ago

Current position

71C717 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 71C717 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 6 distinct

Callsign Airline Flights Last seen
ESR631 - 3 2026-04-13
ESR632 - 2 2026-04-13
ESR603 - 2 2026-04-14
ESR594 Eastar Jet 2 2026-04-13
ESR593 - 2 2026-04-13
ESR604 - 1 2026-04-14

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-14 ESR604 - Apr 14, 10:05 UTCApr 14, 10:55 UTC50m
2026-04-14 ESR603 - Apr 14, 07:35 UTCApr 14, 08:20 UTC45m
2026-04-14 ESR603 - Apr 14, 06:30 UTCApr 14, 07:00 UTC30m
2026-04-13 ESR594 DAD → ICN Apr 13, 19:50 UTCApr 13, 22:00 UTC2h 10m
2026-04-13 ESR594 DAD → ICN Apr 13, 19:15 UTCApr 13, 20:10 UTC55m
2026-04-13 ESR593 - Apr 13, 12:20 UTCApr 13, 15:10 UTC2h 50m
2026-04-13 ESR593 - Apr 13, 12:10 UTCApr 13, 15:10 UTC3h 0m
2026-04-13 ESR632 - Apr 13, 07:55 UTCApr 13, 08:10 UTC15m
2026-04-13 ESR632 - Apr 13, 06:20 UTCApr 13, 08:10 UTC1h 50m
2026-04-13 ESR631 - Apr 13, 04:20 UTCApr 13, 04:35 UTC15m
2026-04-13 ESR631 - Apr 13, 04:10 UTCApr 13, 04:35 UTC25m
2026-04-13 ESR631 - Apr 13, 02:50 UTCApr 13, 04:15 UTC1h 25m

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 HL8717 page for operator, model, and routing details .

Mode-S 71C717 frequently asked

What is Mode-S code 71C717?
71C717 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8717.
Where is Mode-S 71C717 registered?
Mode-S code 71C717 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 71C717 broadcasting right now?
Yes. Mode-S 71C717 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C717, octal 34343427, decimal 7,456,535.
What flights does 71C717 operate?
Mode-S 71C717 has broadcast 6 distinct callsigns, including ESR631, ESR632, ESR603, ESR594, ESR593.