sensors Mode-S transponder

8681AD

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA73NF · BOEING 737-800

Hex
8681AD
Octal
41500655
Decimal
8,815,021
Country
JP
Tail
JA73NF
Type
B738
Broadcasting now · callsign SKY513 · 17,825 ft
Flights observed
13
Distinct callsigns
11
Country
JP
Last broadcast
12h ago

Current position

8681AD is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 8681AD 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 11 distinct

Callsign Airline Flights Last seen
SKY730 - 2 2026-04-13
SKY705 - 2 2026-04-13
SKY710 - 1 2026-04-13
SKY179 - 1 2026-04-13
SKY148 Skymark Airlines 1 2026-04-13
SKY145 - 1 2026-04-13
SKY105 - 1 2026-04-13
SKY022 - 1 2026-04-14
SKY021 Skymark Airlines 1 2026-04-14
SKY012 - 1 2026-04-14
SKY001 - 1 2026-04-13

Recent flights last 13

DateFlightRouteTakeoffLandingDuration
2026-04-14 SKY022 - Apr 14, 10:15 UTCApr 14, 11:05 UTC50m
2026-04-14 SKY021 HND → FUK Apr 14, 07:25 UTCApr 14, 08:40 UTC1h 15m
2026-04-14 SKY012 - Apr 14, 05:25 UTCApr 14, 06:15 UTC50m
2026-04-13 SKY001 - Apr 13, 21:35 UTCApr 13, 22:45 UTC1h 10m
2026-04-13 SKY730 - Apr 13, 12:20 UTCApr 13, 13:25 UTC1h 5m
2026-04-13 SKY730 - Apr 13, 12:10 UTCApr 13, 13:25 UTC1h 15m
2026-04-13 SKY179 - Apr 13, 09:50 UTCApr 13, 11:15 UTC1h 25m
2026-04-13 SKY148 NGS → UKB Apr 13, 08:00 UTCApr 13, 08:35 UTC35m
2026-04-13 SKY145 - Apr 13, 06:00 UTCApr 13, 06:50 UTC50m
2026-04-13 SKY105 - Apr 13, 04:20 UTCApr 13, 05:05 UTC45m
2026-04-13 SKY710 CTS → HND Apr 13, 01:50 UTCApr 13, 03:10 UTC1h 20m
2026-04-13 SKY705 - Apr 13, 00:20 UTCApr 13, 00:55 UTC35m
2026-04-12 SKY705 - Apr 12, 23:55 UTCApr 13, 00:55 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 JA73NF page for operator, model, and routing details .

Mode-S 8681AD frequently asked

What is Mode-S code 8681AD?
8681AD is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA73NF.
Where is Mode-S 8681AD registered?
Mode-S code 8681AD is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8681AD broadcasting right now?
Yes. Mode-S 8681AD is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8681AD, octal 41500655, decimal 8,815,021.
What flights does 8681AD operate?
Mode-S 8681AD has broadcast 11 distinct callsigns, including SKY730, SKY705, SKY710, SKY179, SKY148.