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.
Passenger (Inspected)
FOUR SEA' SONS
MMSI 366939220 · Call sign WY6389
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
14.9 m
Beam
4.3 m
Draft
1.8 m
Call sign
WY6389
Official No.
520093
AIS reports
1
Registered in the United States, FOUR SEA' SONS is a 14.9-metre passenger craft. She has a beam of 4.3 m and a draft measuring 1.8 metres. On the registers she's MMSI 366939220, call sign WY6389. FOUR SEA' SONS can be part of the Master's Mate Safety Initiative Network at no cost — a community watch that never sleeps.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard FOUR SEA' SONS safe.
Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.
Switch on the safety stack — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever FOUR SEA' SONS 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 passenger & charter operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put FOUR SEA' SONS on the map. It hands you the full bridge:
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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.
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.
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 FOUR SEA' SONS and switch it all on
Free to join · nothing to install to start · cancel anytime
About FOUR SEA' SONS
What kind of vessel is FOUR SEA' SONS?
FOUR SEA' SONS is a Passenger (Inspected) flagged to United States of America.
What is FOUR SEA' SONS's MMSI?
FOUR SEA' SONS's MMSI is 366939220. Call sign WY6389.
How big is FOUR SEA' SONS?
FOUR SEA' SONS is about 14.9 m long, 4.3 m on the beam, drawing 1.8 m.
Is FOUR SEA' SONS on the Master's Mate Safety Initiative Network?
Not yet. If FOUR SEA' SONS is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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