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.
Tug
MIHO MARU
MMSI 431002172 · Call sign JD3131
Not yet on Master's MateType
Tug
Flag
JPNLength
34 m
Beam
9 m
Draft
3.6 m
Call sign
JD3131
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
1
On the Japanese registry, MIHO MARU is a 34-metre working tug. MIHO MARU has a beam of 9 m and a 3.6-metre draft. On AIS she shows as MMSI 431002172, call sign JD3131. MIHO MARU can be part of the Master's Mate Safety Initiative Network at no cost — a community watch that never sleeps.
Free forever · No credit card · for working boats
Built for boats that work — like MIHO MARU.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Last known position · Jun 2, 2026
Position
34.9946° N, 138.4995° E
Working 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.
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The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put MIHO MARU on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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.
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 MIHO MARU and switch it all on
Free to join · nothing to install to start · cancel anytime
About MIHO MARU
What kind of vessel is MIHO MARU?
MIHO MARU is a Tug flagged to Japan.
Where was MIHO MARU last seen?
MIHO MARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is MIHO MARU's MMSI?
MIHO MARU's MMSI is 431002172. Call sign JD3131.
How big is MIHO MARU?
MIHO MARU is about 34 m long, 9 m on the beam, drawing 3.6 m.
Is MIHO MARU on the Master's Mate Safety Initiative Network?
Not yet. If MIHO MARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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