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sensors Mode-S transponder

71C737

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

Currently assigned to HL8737 · BOEING 737-800

Hex
71C737
Octal
34343467
Decimal
7,456,567
Country
KR
Tail
HL8737
Type
B738
No current signal · last broadcast Jul 26, 21:45 UTC
Flights observed
449
Distinct callsigns
20
Country
KR
Last broadcast
Jul 26, 21:45 UTC

Last known position

Most recent position reported by Mode-S 71C737.

Country allocation

The ICAO 24-bit address 71C737 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
TWB706 - 9 2026-07-07
TWB703 Tway Airlines 8 2026-07-06
TWB725 - 7 2026-07-17
TWB720 - 7 2026-07-17
TWB688 Tway Airlines 7 2026-07-26
TWB687 Tway Airlines 7 2026-07-26
TWB806 Tway Airlines 6 2026-07-17
TWB803 - 6 2026-07-25
TWB733 - 6 2026-07-06
TWB702 - 6 2026-07-16
TWB668 - 6 2026-07-06
TWB667 - 6 2026-07-06
TWB331 - 6 2026-07-18
TWB320 - 6 2026-07-18
TWB252 - 6 2026-07-02
TWB046 Tway Airlines 6 2026-04-16
TWB809 - 5 2026-07-18
TWB707 - 5 2026-07-17
TWB676 Tway Airlines 5 2026-07-19
TWB664 - 5 2026-07-15

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-26 TWB029 TAE → DAD Jul 26, 12:45 UTCJul 26, 21:45 UTC9h 0m
2026-07-26 TWB808 CJU → TAE Jul 26, 10:05 UTCJul 26, 10:25 UTC20m
2026-07-26 TWB688 TPE → CJU Jul 26, 06:40 UTCJul 26, 07:00 UTC20m
2026-07-26 TWB687 CJU → TPE Jul 26, 04:25 UTCJul 26, 05:00 UTC35m
2026-07-26 TWB807 TAE → CJU Jul 26, 01:25 UTCJul 26, 01:35 UTC10m
2026-07-25 TWB802 CJU → TAE Jul 25, 23:45 UTCJul 26, 00:00 UTC15m
2026-07-25 TWB803 - Jul 25, 21:50 UTCJul 25, 22:05 UTC15m
2026-07-25 TWB9638 HET → TAE Jul 25, 11:10 UTCJul 25, 19:45 UTC8h 35m
2026-07-25 TWB305 ICN → KIX Jul 25, 08:20 UTCJul 25, 09:55 UTC1h 35m
2026-07-25 TWB242 NRT → ICN Jul 25, 04:45 UTCJul 25, 06:40 UTC1h 55m
2026-07-25 TWB241 ICN → NRT Jul 25, 01:10 UTCJul 25, 03:10 UTC2h 0m
2026-07-24 TWB246 NRT → ICN Jul 24, 10:50 UTCJul 24, 12:45 UTC1h 55m
2026-07-24 TWB245 ICN → NRT Jul 24, 07:10 UTCJul 24, 09:05 UTC1h 55m
2026-07-24 TWB302 KIX → ICN Jul 24, 02:50 UTCJul 24, 04:10 UTC1h 20m
2026-07-23 TWB301 ICN → KIX Jul 23, 23:10 UTCJul 24, 00:35 UTC1h 25m
2026-07-23 TWB308 KIX → ICN Jul 23, 15:30 UTCJul 23, 16:55 UTC1h 25m
2026-07-23 TWB307 ICN → KIX Jul 23, 12:25 UTCJul 23, 13:45 UTC1h 20m
2026-07-23 TWB606 - Jul 23, 08:35 UTCJul 23, 09:10 UTC35m
2026-07-23 TWB605 ICN → TNA Jul 23, 05:00 UTCJul 23, 05:25 UTC25m
2026-07-22 TWB9635 ICN → HLD Jul 22, 13:35 UTCJul 22, 19:40 UTC6h 5m
2026-07-22 TWB670 RMQ → ICN Jul 22, 11:10 UTCJul 22, 11:35 UTC25m
2026-07-22 TWB286 HSG → ICN Jul 22, 02:15 UTCJul 22, 03:15 UTC1h 0m
2026-07-21 TWB285 ICN → HSG Jul 21, 23:30 UTCJul 22, 00:30 UTC1h 0m
2026-07-21 TWB670 RMQ → ICN Jul 21, 09:10 UTCJul 21, 11:25 UTC2h 15m
2026-07-21 TWB669 ICN → RMQ Jul 21, 05:30 UTCJul 21, 07:55 UTC2h 25m
2026-07-20 TWB3002 GMP → ICN Jul 20, 22:00 UTCJul 20, 22:45 UTC45m
2026-07-20 TWB270 - Jul 20, 03:35 UTCJul 20, 05:55 UTC2h 20m
2026-07-19 TWB269 - Jul 19, 23:10 UTCJul 20, 01:10 UTC2h 0m
2026-07-19 TWB676 KHH → PUS Jul 19, 09:55 UTCJul 19, 12:10 UTC2h 15m
2026-07-19 TWB675 PUS → KHH Jul 19, 06:15 UTCJul 19, 08:35 UTC2h 20m
2026-07-19 TWB270 - Jul 19, 02:45 UTCJul 19, 05:00 UTC2h 15m
2026-07-18 TWB269 - Jul 18, 23:15 UTCJul 19, 01:25 UTC2h 10m
2026-07-18 TWB640 - Jul 18, 20:45 UTCJul 18, 21:15 UTC30m
2026-07-18 TWB640 - Jul 18, 17:45 UTCJul 18, 19:20 UTC1h 35m
2026-07-18 TWB639 PUS → HKG Jul 18, 13:15 UTCJul 18, 16:05 UTC2h 50m
2026-07-18 TWB320 KIX → PUS Jul 18, 10:20 UTCJul 18, 11:30 UTC1h 10m
2026-07-18 TWB331 - Jul 18, 07:55 UTCJul 18, 09:05 UTC1h 10m
2026-07-18 TWB717 - Jul 18, 05:20 UTCJul 18, 05:55 UTC35m
2026-07-18 TWB718 - Jul 18, 03:30 UTCJul 18, 04:15 UTC45m
2026-07-18 TWB809 - Jul 18, 01:20 UTCJul 18, 01:30 UTC10m
2026-07-17 TWB804 - Jul 17, 23:50 UTCJul 18, 00:19 UTC30m
2026-07-17 TWB803 - Jul 17, 21:50 UTCJul 17, 22:05 UTC15m
2026-07-17 TWB812 - Jul 17, 12:45 UTCJul 17, 13:10 UTC25m
2026-07-17 TWB811 - Jul 17, 10:50 UTCJul 17, 11:04 UTC15m
2026-07-17 TWB806 CJU → TAE Jul 17, 09:15 UTCJul 17, 09:30 UTC15m
2026-07-17 TWB725 - Jul 17, 06:40 UTCJul 17, 07:14 UTC35m
2026-07-17 TWB720 - Jul 17, 04:54 UTCJul 17, 05:30 UTC35m
2026-07-17 TWB707 - Jul 17, 01:00 UTCJul 17, 01:39 UTC40m
2026-07-16 TWB702 - Jul 16, 23:15 UTCJul 16, 23:49 UTC35m
2026-07-16 TWB801 - Jul 16, 21:30 UTCJul 16, 21:45 UTC15m

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 HL8737 page for operator, model, and routing details .

Mode-S 71C737 frequently asked

What is Mode-S code 71C737?
71C737 is an ICAO 24-bit transponder address. Allocated to Korea, South. Assigned to HL8737.
Where is Mode-S 71C737 registered?
Mode-S code 71C737 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 71C737 broadcasting right now?
No active broadcast right now. Last signal was Jul 26, 21:45 UTC.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 71C737, octal 34343467, decimal 7,456,567.
What flights does 71C737 operate?
Mode-S 71C737 has broadcast 20 distinct callsigns, including TWB706, TWB703, TWB725, TWB720, TWB688.