Apparatus

Try JFK, AAL1290, BAW, or N225AN.

sensors Mode-S transponder

840D81

ICAO 24-bit transponder address · allocated to Japan

Currently assigned to JA03RK · BOEING 737-800

Hex
840D81
Octal
41006601
Decimal
8,654,209
Country
JP
Tail
JA03RK
Type
B738
No current signal · last broadcast 47m ago
Flights observed
201
Distinct callsigns
20
Country
JP
Last broadcast
47m ago

Last known position

Most recent position reported by Mode-S 840D81.

Country allocation

The ICAO 24-bit address 840D81 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
JTA1 - 11 2026-05-28
JTA5 - 8 2026-05-29
JTA61 Japan Transocean Air 7 2026-05-26
JTA53 Japan Transocean Air 7 2026-05-15
JTA86 Japan Transocean Air 6 2026-05-27
JTA47 Japan Transocean Air 6 2026-05-16
JTA83 Japan Transocean Air 5 2026-05-10
JTA65 Japan Transocean Air 5 2026-05-26
JTA42 Japan Transocean Air 5 2026-05-16
JTA37 Japan Transocean Air 5 2026-05-11
JTA13 Japan Transocean Air 5 2026-05-10
JTA9 - 4 2026-05-20
JTA60 Japan Transocean Air 4 2026-05-18
JTA54 Japan Transocean Air 4 2026-05-18
JTA4 - 4 2026-05-20
JTA36 Japan Transocean Air 4 2026-05-21
JTA302 Japan Transocean Air 4 2026-05-19
JTA16 Japan Transocean Air 4 2026-05-21
JAL973 Japan Airlines 4 2026-05-24
JTA8 - 3 2026-05-20

Recent flights last 50

DateFlightRouteTakeoffLandingDuration
2026-05-30 JAL933 HND → MMY May 30, 02:06 UTCMay 30, 08:15 UTC6h 9m
2026-05-29 JTA184 KMQ → HND May 29, 23:55 UTCMay 30, 00:45 UTC50m
2026-05-29 JAL183 HND → KMQ May 29, 22:20 UTCMay 29, 23:00 UTC40m
2026-05-29 JTA5 KIX → HND May 29, 05:20 UTCMay 29, 12:55 UTC7h 35m
2026-05-28 JTA1 KIX → KIX May 28, 23:35 UTCMay 29, 04:15 UTC4h 40m
2026-05-27 JTA86 ISG → KIX May 27, 23:45 UTCMay 28, 13:10 UTC13h 25m
2026-05-27 JTA46 OKA → NGO May 27, 12:15 UTCMay 27, 12:55 UTC40m
2026-05-26 JTA65 FUK → OKA May 26, 12:10 UTCMay 26, 12:20 UTC10m
2026-05-26 JTA61 FUK → OKA May 26, 07:05 UTCMay 26, 07:15 UTC10m
2026-05-25 JTA51 FUK → OKA May 25, 22:34 UTCMay 25, 22:44 UTC10m
2026-05-25 JTA52 OKA → FUK May 25, 02:45 UTCMay 25, 02:55 UTC10m
2026-05-24 JAL973 KIX → GMP May 24, 06:05 UTCMay 24, 06:55 UTC50m
2026-05-23 JAL971 KIX → GMP May 23, 22:25 UTCMay 24, 04:55 UTC6h 30m
2026-05-23 JAL192 KMQ → HND May 23, 11:50 UTCMay 23, 12:30 UTC40m
2026-05-23 JAL191 HND → KMQ May 23, 09:40 UTCMay 23, 10:10 UTC30m
2026-05-23 JAL933 HND → MMY May 23, 02:05 UTCMay 23, 08:10 UTC6h 4m
2026-05-23 JAL184 KMQ → HND May 23, 00:00 UTCMay 23, 00:40 UTC40m
2026-05-22 JAL183 HND → KMQ May 22, 22:15 UTCMay 22, 22:40 UTC25m
2026-05-22 JAL974 GMP → KIX May 22, 06:35 UTCMay 22, 13:35 UTC7h 0m
2026-05-21 JTA36 OKA → KMQ May 21, 23:40 UTCMay 22, 05:10 UTC5h 30m
2026-05-21 JTA16 OKA → OKJ May 21, 04:20 UTCMay 21, 12:15 UTC7h 55m
2026-05-21 JTA52 OKA → FUK May 21, 02:35 UTCMay 21, 03:00 UTC25m
2026-05-20 JTA9 - May 20, 13:05 UTCMay 20, 13:20 UTC15m
2026-05-20 JTA9 - May 20, 11:40 UTCMay 20, 12:10 UTC30m
2026-05-20 JTA8 - May 20, 08:45 UTCMay 20, 10:25 UTC1h 40m
2026-05-20 JTA5 - May 20, 06:35 UTCMay 20, 06:50 UTC15m
2026-05-20 JTA5 - May 20, 05:15 UTCMay 20, 05:45 UTC30m
2026-05-20 JTA4 - May 20, 02:35 UTCMay 20, 04:10 UTC1h 35m
2026-05-20 JTA1 - May 20, 01:00 UTCMay 20, 01:15 UTC15m
2026-05-19 JTA1 - May 19, 23:35 UTCMay 20, 00:10 UTC35m
2026-05-19 JTA86 ISG → KIX May 19, 11:25 UTCMay 19, 13:05 UTC1h 40m
2026-05-19 JTA302 TPE → OKA May 19, 02:25 UTCMay 19, 02:45 UTC20m
2026-05-18 JTA301 OKA → TPE May 18, 23:45 UTCMay 19, 00:50 UTC1h 5m
2026-05-18 JTA65 FUK → OKA May 18, 12:50 UTCMay 18, 13:05 UTC15m
2026-05-18 JTA60 OKA → FUK May 18, 09:40 UTCMay 18, 10:00 UTC20m
2026-05-18 JTA61 FUK → OKA May 18, 08:01 UTCMay 18, 08:25 UTC25m
2026-05-18 JTA61 FUK → OKA May 18, 07:05 UTCMay 18, 07:15 UTC10m
2026-05-18 JTA54 OKA → FUK May 18, 04:30 UTCMay 18, 04:51 UTC21m
2026-05-17 JTA45 NGO → OKA May 17, 23:55 UTCMay 18, 01:35 UTC1h 40m
2026-05-17 JTA46 OKA → NGO May 17, 11:15 UTCMay 17, 12:55 UTC1h 40m
2026-05-17 JTA211 OKA → UEO May 17, 04:50 UTCMay 17, 05:00 UTC10m
2026-05-17 JTA1 - May 17, 00:50 UTCMay 17, 01:00 UTC10m
2026-05-16 JTA1 - May 16, 23:30 UTCMay 17, 00:00 UTC30m
2026-05-16 JTA128 MMY → KIX May 16, 11:01 UTCMay 16, 12:45 UTC1h 45m
2026-05-16 JTA47 NGO → OKA May 16, 06:20 UTCMay 16, 07:55 UTC1h 35m
2026-05-16 JTA42 OKA → NGO May 16, 04:50 UTCMay 16, 05:10 UTC20m
2026-05-16 JTA42 OKA → NGO May 16, 03:25 UTCMay 16, 03:40 UTC15m
2026-05-15 JTA65 FUK → OKA May 15, 13:05 UTCMay 15, 13:20 UTC15m
2026-05-15 JTA60 OKA → FUK May 15, 09:40 UTCMay 15, 10:00 UTC20m
2026-05-15 JTA61 FUK → OKA May 15, 07:50 UTCMay 15, 08:20 UTC30m

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 JA03RK page for operator, model, and routing details .

Mode-S 840D81 frequently asked

What is Mode-S code 840D81?
840D81 is an ICAO 24-bit transponder address. Allocated to Japan. Assigned to JA03RK.
Where is Mode-S 840D81 registered?
Mode-S code 840D81 is allocated to Japan (JP). All aircraft registered there receive a Mode-S address from a fixed block defined by ICAO Annex 10.
Is 840D81 broadcasting right now?
No active broadcast right now. Last signal was 47m ago.
Hex, octal, and decimal Mode-S codes: what's the difference?
The same 24-bit identifier expressed in different bases: hex 840D81, octal 41006601, decimal 8,654,209.
What flights does 840D81 operate?
Mode-S 840D81 has broadcast 20 distinct callsigns, including JTA1, JTA5, JTA61, JTA53, JTA86.