sensors Mode-S transponder

851958

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA339J · BOEING 737-800

Hex
851958
Octal
41214530
Decimal
8,722,776
Country
JP
Tail
JA339J
Type
B738
No current signal · last broadcast 2d ago
Flights observed
267
Distinct callsigns
20
Country
JP
Last broadcast
2d ago

Last known position

Most recent position reported by Mode-S 851958.

Country allocation

The ICAO 24-bit address 851958 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

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-28 JAL654 KOJ → HND May 28, 12:20 UTCMay 28, 13:55 UTC1h 35m
2026-05-28 JAL653 HND → KOJ May 28, 09:35 UTCMay 28, 10:45 UTC1h 10m
2026-05-28 JAL612 NGS → HND May 28, 06:50 UTCMay 28, 08:20 UTC1h 30m
2026-05-28 JAL609 HND → NGS May 28, 03:55 UTCMay 28, 05:15 UTC1h 20m
2026-05-28 JAL608 NGS → HND May 28, 01:20 UTCMay 28, 02:40 UTC1h 20m
2026-05-27 JAL605 HND → NGS May 27, 22:50 UTCMay 28, 00:05 UTC1h 15m
2026-05-27 JAL544 KUH → HND May 27, 11:40 UTCMay 27, 13:05 UTC1h 25m
2026-05-27 JAL545 HND → KUH May 27, 09:25 UTCMay 27, 10:30 UTC1h 5m
2026-05-27 JAL648 KOJ → HND May 27, 06:34 UTCMay 27, 07:55 UTC1h 20m
2026-05-27 JAL647 HND → KOJ May 27, 03:39 UTCMay 27, 04:49 UTC1h 10m
2026-05-27 JAL492 KCZ → HND May 27, 00:59 UTCMay 27, 01:44 UTC45m
2026-05-26 JAL491 HND → KCZ May 26, 22:54 UTCMay 26, 23:39 UTC45m
2026-05-26 JAL228 KIX → HND May 26, 12:30 UTCMay 26, 13:19 UTC50m
2026-05-26 JAL2506 CTS → KIX May 26, 09:15 UTCMay 26, 11:05 UTC1h 50m
2026-05-26 JAL2009 ITM → CTS May 26, 06:29 UTCMay 26, 08:15 UTC1h 45m
2026-05-26 JAL2004 CTS → ITM May 26, 03:19 UTCMay 26, 05:00 UTC1h 40m
2026-05-26 JAL509 HND → CTS May 26, 01:05 UTCMay 26, 02:19 UTC1h 15m
2026-05-25 JAL140 AOJ → HND May 25, 22:49 UTCMay 25, 23:45 UTC55m
2026-05-25 JAL151 HND → AOJ May 25, 12:00 UTCMay 25, 12:55 UTC55m
2026-05-25 JAL462 TKS → HND May 25, 09:45 UTCMay 25, 10:55 UTC1h 10m
2026-05-25 JAL461 HND → TKS May 25, 07:35 UTCMay 25, 08:25 UTC50m
2026-05-25 JAL572 OBO → HND May 25, 04:35 UTCMay 25, 05:55 UTC1h 20m
2026-05-25 JAL575 HND → OBO May 25, 02:15 UTCMay 25, 03:05 UTC50m
2026-05-24 JAL623 HND → KMJ May 24, 21:40 UTCMay 24, 21:51 UTC11m
2026-05-24 JAL266 HIJ → HND May 24, 11:50 UTCMay 24, 12:45 UTC55m
2026-05-24 JAL265 HND → HIJ May 24, 09:55 UTCMay 24, 10:55 UTC1h 0m
2026-05-24 JAL376 KKJ → HND May 24, 07:20 UTCMay 24, 08:50 UTC1h 30m
2026-05-24 JAL375 HND → KKJ May 24, 05:00 UTCMay 24, 06:05 UTC1h 5m
2026-05-24 JAL434 MYJ → HND May 24, 02:45 UTCMay 24, 03:50 UTC1h 5m
2026-05-24 JAL433 HND → MYJ May 24, 00:40 UTCMay 24, 01:45 UTC1h 5m
2026-05-23 JAL474 TAK → HND May 23, 22:15 UTCMay 23, 23:05 UTC50m
2026-05-23 JAL487 HND → TAK May 23, 11:35 UTCMay 23, 12:30 UTC55m
2026-05-23 JAL672 OIT → HND May 23, 08:45 UTCMay 23, 09:45 UTC1h 0m
2026-05-23 JAL667 HND → OIT May 23, 06:20 UTCMay 23, 07:25 UTC1h 5m
2026-05-23 JAL456 TKS → HND May 23, 03:30 UTCMay 23, 04:25 UTC55m
2026-05-23 JAL455 HND → TKS May 23, 01:40 UTCMay 23, 02:35 UTC54m
2026-05-22 JAL590 CTS → HND May 22, 22:40 UTCMay 22, 23:55 UTC1h 15m
2026-05-22 JAL599 HND → CTS May 22, 11:55 UTCMay 22, 13:20 UTC1h 25m
2026-05-22 JAL264 HIJ → HND May 22, 09:25 UTCMay 22, 10:30 UTC1h 5m
2026-05-22 JAL3406 CTS → HIJ May 22, 06:20 UTCMay 22, 07:55 UTC1h 35m
2026-05-22 JAL3513 FUK → CTS May 22, 03:10 UTCMay 22, 05:15 UTC2h 5m
2026-05-22 JAL309 HND → FUK May 22, 00:25 UTCMay 22, 02:00 UTC1h 35m
2026-05-21 JAL232 OKJ → HND May 21, 22:20 UTCMay 21, 23:15 UTC55m
2026-05-21 JAL241 HND → OKJ May 21, 11:05 UTCMay 21, 12:00 UTC55m
2026-05-21 JAL240 OKJ → HND May 21, 08:40 UTCMay 21, 09:40 UTC1h 0m
2026-05-21 JAL237 HND → OKJ May 21, 05:45 UTCMay 21, 06:40 UTC55m
2026-05-21 JAL236 OKJ → HND May 21, 03:40 UTCMay 21, 04:35 UTC55m
2026-05-21 JAL233 HND → OKJ May 21, 01:50 UTCMay 21, 02:45 UTC55m
2026-05-20 JAL662 OIT → HND May 20, 23:00 UTCMay 21, 00:15 UTC1h 15m
2026-05-20 JAL671 HND → OIT May 20, 11:50 UTCMay 20, 12:50 UTC1h 0m

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 JA339J page for operator, model, and routing details .

Mode-S 851958 frequently asked

What is Mode-S code 851958?
851958 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA339J.
Where is Mode-S 851958 registered?
Mode-S code 851958 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 851958 broadcasting right now?
No active broadcast right now. Last signal was 2d ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 851958, octal 41214530, decimal 8,722,776.
What flights does 851958 operate?
Mode-S 851958 has broadcast 20 distinct callsigns, including JAL587, JAL586, JAL2505, JAL2501, JAL623.