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
JYOHOUMARU
MMSI 431003435 · Call sign JD3329
Not yet on Master's MateType
Tanker
Flag
JPNLength
105 m
Beam
16 m
Draft
6.9 m
Call sign
JD3329
IMO
9634866
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
22
JYOHOUMARU flies the Japanese flag — a 105-metre tank vessel. JYOHOUMARU has 16 metres in the beam and a 6.9 m draft. On the registers she's MMSI 431003435, call sign JD3329, IMO 9634866. It's free to add JYOHOUMARU to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
Free forever · No credit card · for commercial operators
Eyes on JYOHOUMARU, 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
38.2727° N, 141.0030° E
Transiting the Sea of Japan? You're never out there alone.
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The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put JYOHOUMARU 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 JYOHOUMARU and switch it all on
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About JYOHOUMARU
What kind of vessel is JYOHOUMARU?
JYOHOUMARU is a Tanker flagged to Japan.
Where was JYOHOUMARU last seen?
JYOHOUMARU was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is JYOHOUMARU's MMSI?
JYOHOUMARU's MMSI is 431003435. Call sign JD3329. IMO 9634866.
How big is JYOHOUMARU?
JYOHOUMARU is about 105 m long, 16 m on the beam, drawing 6.9 m.
Is JYOHOUMARU on the Master's Mate Safety Initiative Network?
Not yet. If JYOHOUMARU is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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