sensors Mode-S transponder

8681B2

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA73NL · BOEING 737-800

Hex
8681B2
Octal
41500662
Decimal
8,815,026
Country
JP
Tail
JA73NL
Type
B738
Broadcasting now · callsign SKY135 · 28,000 ft
Flights observed
490
Distinct callsigns
20
Country
JP
Last broadcast
1h ago

Current position

8681B2 is currently broadcasting. Map zoomed to live position.

Country allocation

The ICAO 24-bit address 8681B2 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

Callsign Airline Flights Last seen
SKY597 - 10 2026-07-09
SKY512 - 8 2026-06-23
SKY018 - 8 2026-06-16
SKY720 - 7 2026-06-24
SKY717 - 7 2026-06-24
SKY712 - 7 2026-06-23
SKY303 - 7 2026-06-16
SKY175 - 7 2026-06-23
SKY147 - 7 2026-06-22
SKY113 - 7 2026-06-22
SKY015 - 7 2026-06-16
SKY014 - 7 2026-06-22
SKY011 - 7 2026-06-22
SKY613 - 6 2026-07-09
SKY558 Skymark Airlines 6 2026-07-09
SKY302 - 6 2026-06-22
SKY140 - 6 2026-06-22
SKY730 - 5 2026-07-03
SKY729 Skymark Airlines 5 2026-07-08
SKY591 - 5 2026-07-08

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-07-14 SKY136 - Jul 14, 05:00 UTCJul 14, 05:40 UTC40m
2026-07-14 SKY637 - Jul 14, 03:00 UTCJul 14, 03:40 UTC40m
2026-07-14 SKY762 - Jul 14, 00:35 UTCJul 14, 01:50 UTC1h 15m
2026-07-13 SKY761 - Jul 13, 22:20 UTCJul 13, 23:45 UTC1h 25m
2026-07-13 SKY768 - Jul 13, 13:10 UTCJul 13, 14:20 UTC1h 10m
2026-07-13 SKY727 - Jul 13, 10:50 UTCJul 13, 12:05 UTC1h 15m
2026-07-13 SKY112 - Jul 13, 08:45 UTCJul 13, 09:45 UTC1h 0m
2026-07-13 SKY185 - Jul 13, 05:25 UTCJul 13, 06:25 UTC1h 0m
2026-07-13 SKY184 - Jul 13, 03:40 UTCJul 13, 04:35 UTC55m
2026-07-13 SKY170 - Jul 13, 01:25 UTCJul 13, 02:50 UTC1h 25m
2026-07-12 SKY171 UKB → CTS Jul 12, 22:45 UTCJul 13, 00:25 UTC1h 40m
2026-07-12 SKY178 - Jul 12, 12:05 UTCJul 12, 13:30 UTC1h 25m
2026-07-12 SKY795 - Jul 12, 09:50 UTCJul 12, 11:10 UTC1h 20m
2026-07-12 SKY532 - Jul 12, 06:45 UTCJul 12, 08:55 UTC2h 10m
2026-07-12 SKY163 - Jul 12, 02:05 UTCJul 12, 03:40 UTC1h 35m
2026-07-12 SKY132 - Jul 12, 00:25 UTCJul 12, 01:05 UTC40m
2026-07-11 SKY301 - Jul 11, 21:55 UTCJul 11, 22:55 UTC1h 0m
2026-07-11 SKY520 - Jul 11, 14:40 UTCJul 11, 15:20 UTC40m
2026-07-11 SKY520 - Jul 11, 13:15 UTCJul 11, 13:30 UTC15m
2026-07-11 SKY5525 - Jul 11, 10:15 UTCJul 11, 12:20 UTC2h 5m
2026-07-11 SKY7017 - Jul 11, 06:01 UTCJul 11, 06:40 UTC40m
2026-07-09 SKY558 OKA → NGO Jul 9, 13:35 UTCJul 9, 13:55 UTC20m
2026-07-09 SKY558 OKA → NGO Jul 9, 12:15 UTCJul 9, 12:30 UTC15m
2026-07-09 SKY597 - Jul 9, 10:50 UTCJul 9, 11:00 UTC10m
2026-07-09 SKY597 - Jul 9, 09:25 UTCJul 9, 10:05 UTC40m
2026-07-09 SKY613 HND → UKB Jul 9, 02:45 UTCJul 9, 08:35 UTC5h 50m
2026-07-08 SKY706 - Jul 8, 23:25 UTCJul 9, 00:40 UTC1h 15m
2026-07-08 SKY729 HND → CTS Jul 8, 12:20 UTCJul 8, 13:35 UTC1h 15m
2026-07-08 SKY618 - Jul 8, 09:10 UTCJul 8, 11:25 UTC2h 15m
2026-07-08 SKY591 - Jul 8, 00:05 UTCJul 8, 00:20 UTC15m
2026-07-07 SKY591 - Jul 7, 22:40 UTCJul 7, 23:15 UTC35m
2026-07-07 SKY596 - Jul 7, 11:10 UTCJul 7, 11:55 UTC45m
2026-07-07 SKY596 - Jul 7, 10:15 UTCJul 7, 10:25 UTC10m
2026-07-07 SKY519 - Jul 7, 07:00 UTCJul 7, 09:05 UTC2h 5m
2026-07-07 SKY108 - Jul 7, 04:10 UTCJul 7, 05:00 UTC50m
2026-07-07 SKY142 - Jul 7, 02:30 UTCJul 7, 03:20 UTC50m
2026-07-07 SKY141 - Jul 7, 00:40 UTCJul 7, 01:30 UTC50m
2026-07-06 SKY183 - Jul 6, 22:45 UTCJul 6, 23:45 UTC1h 0m
2026-07-06 SKY836 - Jul 6, 09:50 UTCJul 6, 11:15 UTC1h 25m
2026-07-06 SKY564 - Jul 6, 08:20 UTCJul 6, 08:35 UTC15m
2026-07-06 SKY563 - Jul 6, 05:10 UTCJul 6, 07:45 UTC2h 35m
2026-07-06 SKY831 - Jul 6, 01:10 UTCJul 6, 02:30 UTC1h 20m
2026-07-05 SKY182 - Jul 5, 23:20 UTCJul 6, 00:20 UTC1h 0m
2026-07-05 SKY138 - Jul 5, 11:50 UTCJul 5, 12:35 UTC45m
2026-07-05 SKY135 - Jul 5, 06:40 UTCJul 5, 07:15 UTC35m
2026-07-05 SKY136 - Jul 5, 05:05 UTCJul 5, 05:50 UTC45m
2026-07-05 SKY637 - Jul 5, 03:15 UTCJul 5, 03:30 UTC15m
2026-07-05 SKY762 - Jul 5, 00:35 UTCJul 5, 02:05 UTC1h 30m
2026-07-04 SKY761 - Jul 4, 22:20 UTCJul 4, 23:40 UTC1h 20m
2026-07-04 SKY768 - Jul 4, 11:50 UTCJul 4, 13:00 UTC1h 10m

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 JA73NL page for operator, model, and routing details .

Mode-S 8681B2 frequently asked

What is Mode-S code 8681B2?
8681B2 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA73NL.
Where is Mode-S 8681B2 registered?
Mode-S code 8681B2 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 8681B2 broadcasting right now?
Yes. Mode-S 8681B2 is currently airborne.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 8681B2, octal 41500662, decimal 8,815,026.
What flights does 8681B2 operate?
Mode-S 8681B2 has broadcast 20 distinct callsigns, including SKY597, SKY512, SKY018, SKY720, SKY717.