sensors Mode-S transponder

851CA8

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA347J · BOEING 737-800

Hex
851CA8
Octal
41216250
Decimal
8,723,624
Country
JP
Tail
JA347J
Type
B738
No current signal · last broadcast 12h ago
Flights observed
12
Distinct callsigns
9
Country
JP
Last broadcast
12h ago

Last known position

Most recent position reported by Mode-S 851CA8.

Country allocation

The ICAO 24-bit address 851CA8 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 9 distinct

Callsign Airline Flights Last seen
JL2004 Japan Airlines 3 2026-04-13
JAL437 - 2 2026-04-14
JAL662 - 1 2026-04-12
JAL509 - 1 2026-04-13
JAL438 Japan Airlines 1 2026-04-14
JAL2506 - 1 2026-04-13
JAL228 - 1 2026-04-13
JAL2009 - 1 2026-04-13
JAL141 - 1 2026-04-13

Recent flights last 12

DateFlightRouteTakeoffLandingDuration
2026-04-14 JAL438 MYJ → HND Apr 14, 09:15 UTCApr 14, 10:15 UTC1h 0m
2026-04-14 JAL437 - Apr 14, 07:10 UTCApr 14, 07:40 UTC30m
2026-04-14 JAL437 - Apr 14, 06:45 UTCApr 14, 07:10 UTC25m
2026-04-13 JAL141 - Apr 13, 22:45 UTCApr 13, 23:35 UTC50m
2026-04-13 JAL228 - Apr 13, 12:40 UTCApr 13, 13:30 UTC50m
2026-04-13 JAL2506 - Apr 13, 09:05 UTCApr 13, 10:05 UTC1h 0m
2026-04-13 JAL2009 - Apr 13, 06:30 UTCApr 13, 08:00 UTC1h 30m
2026-04-13 JL2004 CTS → ITM Apr 13, 04:20 UTCApr 13, 05:00 UTC40m
2026-04-13 JL2004 CTS → ITM Apr 13, 03:55 UTCApr 13, 05:00 UTC1h 5m
2026-04-13 JL2004 CTS → ITM Apr 13, 03:20 UTCApr 13, 04:15 UTC55m
2026-04-13 JAL509 HND → CTS Apr 13, 01:10 UTCApr 13, 02:25 UTC1h 15m
2026-04-12 JAL662 - Apr 12, 23:55 UTCApr 13, 00:05 UTC10m

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 JA347J page for operator, model, and routing details .

Mode-S 851CA8 frequently asked

What is Mode-S code 851CA8?
851CA8 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA347J.
Where is Mode-S 851CA8 registered?
Mode-S code 851CA8 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 851CA8 broadcasting right now?
No active broadcast right now. Last signal was 12h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 851CA8, octal 41216250, decimal 8,723,624.
What flights does 851CA8 operate?
Mode-S 851CA8 has broadcast 9 distinct callsigns, including JL2004, JAL437, JAL662, JAL509, JAL438.