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.
Towing Vessel
Mary B
MMSI 367703290 · Call sign WDI4907
Not yet on Master's MateType
Towing Vessel
Flag
USALength
14.4 m
Beam
5.5 m
Draft
2 m
Call sign
WDI4907
Official No.
563626
AIS reports
1
An American work boat, Mary B measures 14.4 metres. Her hull carries a beam measuring 5.5 metres and a draft measuring 2 metres. Find her under MMSI 367703290, call sign WDI4907. Add Mary B to the Master's Mate Safety Initiative Network — free to join, and the fleet keeps an eye out for each other.
Free forever · No credit card · for working boats
Built for boats that work — like Mary B.
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
Wherever Mary B 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 working boats
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Mary B 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 Mary B and switch it all on
Free to join · nothing to install to start · cancel anytime
About Mary B
What kind of vessel is Mary B?
Mary B is a Towing Vessel flagged to United States of America.
What is Mary B's MMSI?
Mary B's MMSI is 367703290. Call sign WDI4907.
How big is Mary B?
Mary B is about 14.4 m long, 5.5 m on the beam, drawing 2 m.
Is Mary B on the Master's Mate Safety Initiative Network?
Not yet. If Mary B is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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