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
OUKOUMARU
MMSI 431012947 · Call sign JD4552
Not yet on Master's MateType
Cargo
Flag
JPNLength
76 m
Beam
12 m
Draft
4.3 m
Call sign
JD4552
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
49
OUKOUMARU, an ocean freighter flagged in Japan, measures 76 metres on deck. Below, she has a beam of 12 m and a draft of 4.3 m. Find her under MMSI 431012947, call sign JD4552. Claim OUKOUMARU free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.
Free forever · No credit card · for commercial operators
Eyes on OUKOUMARU, 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 4, 2026
Position
34.2285° N, 135.1274° E
Transiting the Sea of Japan? You're never out there alone.
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Joining the Safety Initiative Network doesn't just put OUKOUMARU 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 OUKOUMARU and switch it all on
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About OUKOUMARU
What kind of vessel is OUKOUMARU?
OUKOUMARU is a Cargo flagged to Japan.
Where was OUKOUMARU last seen?
OUKOUMARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is OUKOUMARU's MMSI?
OUKOUMARU's MMSI is 431012947. Call sign JD4552.
How big is OUKOUMARU?
OUKOUMARU is about 76 m long, 12 m on the beam, drawing 4.3 m.
Is OUKOUMARU on the Master's Mate Safety Initiative Network?
Not yet. If OUKOUMARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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