sensors Mode-S transponder

841F65

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA08RK · BOEING 737-800

Hex
841F65
Octal
41017545
Decimal
8,658,789
Country
JP
Tail
JA08RK
Type
B738
Broadcasting now · callsign JTA50 · 15,425 ft
Flights observed
6
Distinct callsigns
5
Country
JP
Last broadcast
15h ago

Current position

841F65 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 841F65 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 5 distinct

Callsign Airline Flights Last seen
JTA49 - 2 2026-04-13
JTA614 - 1 2026-04-13
JTA562 Japan Transocean Air 1 2026-04-14
JTA44 - 1 2026-04-13
JTA121 - 1 2026-04-13

Recent flights last 6

DateFlightRouteTakeoffLandingDuration
2026-04-14 JTA562 MMY → OKA Apr 14, 07:40 UTCApr 14, 07:55 UTC15m
2026-04-13 JTA49 - Apr 13, 11:55 UTCApr 13, 12:10 UTC15m
2026-04-13 JTA49 - Apr 13, 11:40 UTCApr 13, 12:10 UTC30m
2026-04-13 JTA44 - Apr 13, 07:35 UTCApr 13, 07:55 UTC20m
2026-04-13 JTA614 - Apr 13, 05:55 UTCApr 13, 06:05 UTC10m
2026-04-13 JTA121 - Apr 13, 00:20 UTCApr 13, 00:40 UTC20m

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 JA08RK page for operator, model, and routing details .

Mode-S 841F65 frequently asked

What is Mode-S code 841F65?
841F65 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA08RK.
Where is Mode-S 841F65 registered?
Mode-S code 841F65 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 841F65 broadcasting right now?
Yes. Mode-S 841F65 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 841F65, octal 41017545, decimal 8,658,789.
What flights does 841F65 operate?
Mode-S 841F65 has broadcast 5 distinct callsigns, including JTA49, JTA614, JTA562, JTA44, JTA121.