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.
Freight Ship
John Calvin
MMSI 367054310 · Call sign WDC6308
Not yet on Master's MateType
Freight Ship
Flag
USALength
18.5 m
Beam
6.5 m
Draft
1.6 m
Call sign
WDC6308
IMO
8134314
Official No.
623793
AIS reports
1
John Calvin is an American cargo vessel, 18.5 metres overall. She carries a 6.5 m beam and a 1.6-metre draft. Her papers read MMSI 367054310, call sign WDC6308, IMO 8134314. Give John Calvin the backing of the Master's Mate Safety Initiative Network — free, and a fleet that has her back.
Free forever · No credit card · for commercial operators
Eyes on John Calvin, 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
Wherever John Calvin roams, 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 John Calvin 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 John Calvin and switch it all on
Free to join · nothing to install to start · cancel anytime
About John Calvin
What kind of vessel is John Calvin?
John Calvin is a Freight Ship flagged to United States of America.
What is John Calvin's MMSI?
John Calvin's MMSI is 367054310. Call sign WDC6308. IMO 8134314.
How big is John Calvin?
John Calvin is about 18.5 m long, 6.5 m on the beam, drawing 1.6 m.
Is John Calvin on the Master's Mate Safety Initiative Network?
Not yet. If John Calvin is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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