sensors Mode-S transponder

841FDC

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA08WJ · AIRBUS A-350-1000

Hex
841FDC
Octal
41017734
Decimal
8,658,908
Country
JP
Tail
JA08WJ
Type
A35K
No current signal · last broadcast 18h ago
Flights observed
5
Distinct callsigns
2
Country
JP
Last broadcast
18h ago

Last known position

Most recent position reported by Mode-S 841FDC.

Country allocation

The ICAO 24-bit address 841FDC 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 2 distinct

Callsign Airline Flights Last seen
JAL46 - 3 2026-04-13
JAL43 Japan Airlines 2 2026-04-14

Recent flights last 5

DateFlightRouteTakeoffLandingDuration
2026-04-14 JAL43 HND → LHR Apr 14, 07:10 UTCApr 14, 07:25 UTC15m
2026-04-14 JAL43 HND → LHR Apr 14, 06:35 UTCApr 14, 07:10 UTC35m
2026-04-13 JAL46 - Apr 13, 07:55 UTCApr 13, 08:00 UTC5m
2026-04-13 JAL46 - Apr 13, 06:00 UTCApr 13, 08:00 UTC2h 0m
2026-04-12 JAL46 - Apr 12, 18:55 UTCApr 12, 20:15 UTC1h 20m

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 JA08WJ page for operator, model, and routing details .

Mode-S 841FDC frequently asked

What is Mode-S code 841FDC?
841FDC is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA08WJ.
Where is Mode-S 841FDC registered?
Mode-S code 841FDC is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 841FDC broadcasting right now?
No active broadcast right now. Last signal was 18h ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 841FDC, octal 41017734, decimal 8,658,908.
What flights does 841FDC operate?
Mode-S 841FDC has broadcast 2 distinct callsigns, including JAL46, JAL43.