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
William B
MMSI 367685540 · Call sign WDI3157
Not yet on Master's MateType
Towing Vessel
Flag
USALength
16.1 m
Beam
5.5 m
Draft
1.9 m
Call sign
WDI3157
Official No.
561219
AIS reports
1
On the American registry, William B is a 16.1-metre workboat. She carries a beam measuring 5.5 metres and a 1.9 m draft. Look for MMSI 367685540, call sign WDI3157. William B earns her keep on the water; the free Master's Mate Safety Initiative Network keeps a watching fleet and a distress mesh close at hand.
Free forever · No credit card · for working boats
Built for boats that work — like William 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 William 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 William 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 William B and switch it all on
Free to join · nothing to install to start · cancel anytime
About William B
What kind of vessel is William B?
William B is a Towing Vessel flagged to United States of America.
What is William B's MMSI?
William B's MMSI is 367685540. Call sign WDI3157.
How big is William B?
William B is about 16.1 m long, 5.5 m on the beam, drawing 1.9 m.
Is William B on the Master's Mate Safety Initiative Network?
Not yet. If William B is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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