Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Cargo
KOUSEI MARU
MMSI 431013385 · Call sign JD4618
Not yet on Master's MateType
Cargo
Flag
JPNLength
74 m
Beam
12 m
Draft
4.2 m
Call sign
JD4618
IMO
9882932
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
25
KOUSEI MARU is a Japanese ocean freighter, 74 metres LOA. Her hull carries 12 metres in the beam and a draft of 4.2 m. Officially she's MMSI 431013385, call sign JD4618, IMO 9882932. Give KOUSEI MARU the backing of the Master's Mate Safety Initiative Network — free, and a fleet that has her back.
Free forever · No credit card · for commercial operators
Eyes on KOUSEI MARU, around the clock.
Real-time AIS, full systems telemetry, distress alerting and worldwide charts — your hull on one dashboard, from anywhere.
Put her on the dashboard — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Last known position · Jun 2, 2026
Position
35.9266° N, 140.6618° E
Transiting the Sea of Japan? You're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
Free with your claim · for commercial operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put KOUSEI MARU on the map. It hands you the full bridge:
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim KOUSEI MARU and switch it all on
Free to join · nothing to install to start · cancel anytime
About KOUSEI MARU
What kind of vessel is KOUSEI MARU?
KOUSEI MARU is a Cargo flagged to Japan.
Where was KOUSEI MARU last seen?
KOUSEI MARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is KOUSEI MARU's MMSI?
KOUSEI MARU's MMSI is 431013385. Call sign JD4618. IMO 9882932.
How big is KOUSEI MARU?
KOUSEI MARU is about 74 m long, 12 m on the beam, drawing 4.2 m.
Is KOUSEI MARU on the Master's Mate Safety Initiative Network?
Not yet. If KOUSEI MARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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