sensors Mode-S transponder

8515C4

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA329J · BOEING 737-800

Hex
8515C4
Octal
41212704
Decimal
8,721,860
Country
JP
Tail
JA329J
Type
B738
Transponder active on ground
Flights observed
232
Distinct callsigns
20
Country
JP
Last broadcast
2h ago

Last known position

Most recent position reported by Mode-S 8515C4.

Country allocation

The ICAO 24-bit address 8515C4 falls within the block assigned to Japan (JP) by ICAO Annex 10, Volume III. Every aircraft registered in Japan 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
JA329J - 16 2026-05-23
JAL263 Japan Airlines 6 2026-05-29
JAL262 Japan Airlines 6 2026-05-29
JAL668 Japan Airlines 5 2026-05-29
JAL663 Japan Airlines 5 2026-05-29
JAL486 Japan Airlines 4 2026-05-29
JAL485 Japan Airlines 4 2026-05-29
JAL187 Japan Airlines 4 2026-05-28
JAL690 Japan Airlines 3 2026-05-28
JAL687 Japan Airlines 3 2026-05-27
JAL498 Japan Airlines 3 2026-05-12
JAL193 Japan Airlines 3 2026-05-28
JAL190 Japan Airlines 3 2026-05-28
JAL189 Japan Airlines 3 2026-05-28
JAL188 Japan Airlines 3 2026-05-28
JAL182 Japan Airlines 3 2026-05-28
JAL698 Japan Airlines 2 2026-05-09
JAL695 Japan Airlines 2 2026-05-09
JAL674 Japan Airlines 2 2026-05-10
JAL670 Japan Airlines 2 2026-05-12

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-29 JAL623 HND → KMJ May 29, 21:40 UTCMay 29, 23:00 UTC1h 20m
2026-05-29 JAL486 TAK → HND May 29, 12:00 UTCMay 29, 12:55 UTC55m
2026-05-29 JAL485 HND → TAK May 29, 10:10 UTCMay 29, 11:05 UTC55m
2026-05-29 JAL262 HIJ → HND May 29, 08:00 UTCMay 29, 09:00 UTC1h 0m
2026-05-29 JAL263 HND → HIJ May 29, 05:55 UTCMay 29, 07:00 UTC1h 5m
2026-05-29 JAL668 OIT → HND May 29, 03:35 UTCMay 29, 04:45 UTC1h 10m
2026-05-29 JAL663 HND → OIT May 29, 01:00 UTCMay 29, 02:05 UTC1h 5m
2026-05-28 JAL182 KMQ → HND May 28, 22:55 UTCMay 28, 23:50 UTC55m
2026-05-28 JAL193 HND → KMQ May 28, 12:05 UTCMay 28, 12:45 UTC40m
2026-05-28 JAL190 KMQ → HND May 28, 09:55 UTCMay 28, 10:55 UTC1h 0m
2026-05-28 JAL189 HND → KIX May 28, 08:20 UTCMay 28, 09:00 UTC40m
2026-05-28 JAL188 KMQ → HND May 28, 06:00 UTCMay 28, 07:00 UTC1h 0m
2026-05-28 JAL187 HND → KMQ May 28, 04:20 UTCMay 28, 05:00 UTC40m
2026-05-28 JAL690 KMI → HND May 28, 02:15 UTCMay 28, 03:05 UTC50m
2026-05-27 JAL687 HND → KMI May 27, 23:30 UTCMay 28, 00:10 UTC40m
2026-05-27 JAL566 MMB → HND May 27, 10:55 UTCMay 27, 12:25 UTC1h 30m
2026-05-27 JAL569 HND → MMB May 27, 08:55 UTCMay 27, 10:15 UTC1h 20m
2026-05-27 JAL586 HKD → HND May 27, 06:15 UTCMay 27, 07:20 UTC1h 6m
2026-05-27 JAL587 HND → HKD May 27, 04:09 UTCMay 27, 05:09 UTC1h 0m
2026-05-27 JAL664 OIT → HND May 27, 02:04 UTCMay 27, 03:04 UTC1h 0m
2026-05-26 JAL638 KMJ → HND May 26, 11:30 UTCMay 26, 12:35 UTC1h 5m
2026-05-26 JAL637 HND → KMJ May 26, 08:54 UTCMay 26, 10:14 UTC1h 20m
2026-05-26 JAL542 KUH → HND May 26, 05:59 UTCMay 26, 07:24 UTC1h 25m
2026-05-26 JAL543 HND → KUH May 26, 03:35 UTCMay 26, 04:39 UTC1h 5m
2026-05-26 JAL234 OKJ → HND May 26, 01:34 UTCMay 26, 02:29 UTC55m
2026-05-25 JAL231 HND → OKJ May 25, 23:40 UTCMay 26, 00:29 UTC50m
2026-05-25 JAL4104 - May 25, 02:00 UTCMay 25, 02:30 UTC30m
2026-05-23 JA329J - May 23, 05:00 UTCMay 23, 06:10 UTC1h 10m
2026-05-23 JA329J - May 23, 01:05 UTCMay 23, 02:25 UTC1h 20m
2026-05-22 JA329J - May 22, 04:40 UTCMay 22, 06:00 UTC1h 20m
2026-05-22 JA329J - May 22, 01:15 UTCMay 22, 02:45 UTC1h 30m
2026-05-21 JA329J - May 21, 07:00 UTCMay 21, 08:25 UTC1h 25m
2026-05-21 JA329J - May 21, 04:50 UTCMay 21, 06:05 UTC1h 15m
2026-05-21 JA329J - May 21, 01:45 UTCMay 21, 03:15 UTC1h 30m
2026-05-20 JA329J - May 20, 07:05 UTCMay 20, 08:20 UTC1h 15m
2026-05-20 JA329J - May 20, 04:40 UTCMay 20, 06:20 UTC1h 40m
2026-05-20 JA329J - May 20, 01:10 UTCMay 20, 02:30 UTC1h 20m
2026-05-19 JA329J - May 19, 04:40 UTCMay 19, 06:15 UTC1h 35m
2026-05-19 JA329J - May 19, 01:05 UTCMay 19, 02:40 UTC1h 35m
2026-05-18 JA329J - May 18, 04:40 UTCMay 18, 06:01 UTC1h 20m
2026-05-18 JA329J - May 18, 01:20 UTCMay 18, 02:40 UTC1h 20m
2026-05-17 JA329J HKD → HKD May 17, 04:45 UTCMay 17, 06:20 UTC1h 35m
2026-05-17 JA329J - May 17, 01:25 UTCMay 17, 02:50 UTC1h 25m
2026-05-16 JAL4103 NRT → HKD May 16, 02:35 UTCMay 16, 03:40 UTC1h 5m
2026-05-15 JAL242 OKJ → HND May 15, 10:40 UTCMay 15, 11:45 UTC1h 5m
2026-05-15 JAL239 HND → OKJ May 15, 08:45 UTCMay 15, 09:35 UTC50m
2026-05-15 JAL482 TAK → HND May 15, 06:30 UTCMay 15, 07:35 UTC1h 5m
2026-05-15 JAL481 HND → TAK May 15, 04:35 UTCMay 15, 05:20 UTC45m
2026-05-15 JAL186 KIX → HND May 15, 02:40 UTCMay 15, 03:25 UTC45m
2026-05-15 JAL185 HND → KMQ May 15, 00:40 UTCMay 15, 01:05 UTC25m

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 JA329J page for operator, model, and routing details .

Mode-S 8515C4 frequently asked

What is Mode-S code 8515C4?
8515C4 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA329J.
Where is Mode-S 8515C4 registered?
Mode-S code 8515C4 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8515C4 broadcasting right now?
Mode-S 8515C4 is currently broadcasting from the ground.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8515C4, octal 41212704, decimal 8,721,860.
What flights does 8515C4 operate?
Mode-S 8515C4 has broadcast 20 distinct callsigns, including JA329J, JAL263, JAL262, JAL668, JAL663.