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.
Tanker
YOUWAMARU
MMSI 431010077 · Call sign JD4248
Not yet on Master's MateType
Tanker
Flag
JPNLength
105 m
Beam
16 m
Draft
6.5 m
Call sign
JD4248
IMO
9810173
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
29
YOUWAMARU, a tanker hailing from Japan, measures 105 metres on deck. She's built with a beam measuring 16 metres and a 6.5-metre draft. On AIS she shows as MMSI 431010077, call sign JD4248, IMO 9810173. Add YOUWAMARU to the Master's Mate Safety Initiative Network and share the water with a fleet that's paying attention — free.
Free forever · No credit card · for commercial operators
Eyes on YOUWAMARU, 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 3, 2026
Position
35.4604° N, 139.8070° 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 YOUWAMARU 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 YOUWAMARU and switch it all on
Free to join · nothing to install to start · cancel anytime
About YOUWAMARU
What kind of vessel is YOUWAMARU?
YOUWAMARU is a Tanker flagged to Japan.
Where was YOUWAMARU last seen?
YOUWAMARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is YOUWAMARU's MMSI?
YOUWAMARU's MMSI is 431010077. Call sign JD4248. IMO 9810173.
How big is YOUWAMARU?
YOUWAMARU is about 105 m long, 16 m on the beam, drawing 6.5 m.
Is YOUWAMARU on the Master's Mate Safety Initiative Network?
Not yet. If YOUWAMARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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