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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.
Vessel

Koushomaru

MMSI 431011131

Not yet on Master's Mate
Flag
JPNJPN
Length
120.5 m
IMO
9824447
AIS reports
2

Koushomaru is a craft wearing Japanese colours, 120.5 metres long. Find her under MMSI 431011131, IMO 9824447. Claim Koushomaru free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.

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Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.

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Wherever Koushomaru roams, you're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
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Joining the Safety Initiative Network doesn't just put Koushomaru on the map. It hands you the full bridge:

Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
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.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim Koushomaru and switch it all on
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About Koushomaru

What kind of vessel is Koushomaru?
Koushomaru is a vessel flagged to Japan.
What is Koushomaru's MMSI?
Koushomaru's MMSI is 431011131. IMO 9824447.
How big is Koushomaru?
Koushomaru is about 120.5 m long.
Is Koushomaru on the Master's Mate Safety Initiative Network?
Not yet. If Koushomaru is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).

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