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
Sheila Johnson
MMSI 366974180 · Call sign WDB9350
Not yet on Master's MateType
Towing Vessel
Flag
USALength
40.9 m
Beam
14.6 m
Draft
3.3 m
Call sign
WDB9350
Official No.
566984
AIS reports
1
Sheila Johnson, a workboat wearing American colours, measures 40.9 metres on deck. She carries a 14.6 m beam and a 3.3 m draft. On the registers she's MMSI 366974180, call sign WDB9350. Join Sheila Johnson to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.
Free forever · No credit card · for working boats
Built for boats that work — like Sheila Johnson.
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 Sheila Johnson 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 Sheila Johnson 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 Sheila Johnson and switch it all on
Free to join · nothing to install to start · cancel anytime
About Sheila Johnson
What kind of vessel is Sheila Johnson?
Sheila Johnson is a Towing Vessel flagged to United States of America.
What is Sheila Johnson's MMSI?
Sheila Johnson's MMSI is 366974180. Call sign WDB9350.
How big is Sheila Johnson?
Sheila Johnson is about 40.9 m long, 14.6 m on the beam, drawing 3.3 m.
Is Sheila Johnson on the Master's Mate Safety Initiative Network?
Not yet. If Sheila Johnson is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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