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
Big John
MMSI 367338920 · Call sign WDE3426
Not yet on Master's MateType
Towing Vessel
Flag
USALength
15.5 m
Beam
5.5 m
Draft
1.9 m
Call sign
WDE3426
Official No.
507159
AIS reports
1
An American utility vessel, Big John measures 15.5 metres. Big John has a beam of 5.5 m and a 1.9-metre draft. Her registration reads MMSI 367338920, call sign WDE3426. Working vessels like Big John are never truly alone on the Master's Mate Safety Initiative Network — free, with a fleet on watch.
Free forever · No credit card · for working boats
Built for boats that work — like Big John.
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 Big John 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 Big John 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 Big John and switch it all on
Free to join · nothing to install to start · cancel anytime
About Big John
What kind of vessel is Big John?
Big John is a Towing Vessel flagged to United States of America.
What is Big John's MMSI?
Big John's MMSI is 367338920. Call sign WDE3426.
How big is Big John?
Big John is about 15.5 m long, 5.5 m on the beam, drawing 1.9 m.
Is Big John on the Master's Mate Safety Initiative Network?
Not yet. If Big John is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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