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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.
Vessel

SIO 1

MMSI 367075040 · Call sign WXD5803

Not yet on Master's Mate
Flag
USAUSA
Call sign
WXD5803
Official No.
CF0873XS
AIS reports
1

SIO 1 is an American vessel. Officially she's MMSI 367075040, call sign WXD5803. SIO 1 can join the Master's Mate Safety Initiative Network for free: think of it as a watch network that has every boat's back.

Free forever · No credit card

Is SIO 1 your boat?

Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.

Claim this boat — free →

Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers

Wherever SIO 1 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

The most powerful cruising platform ever built — yours, free.

Joining the Safety Initiative Network doesn't just put SIO 1 on the map. It hands you the full bridge:

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.
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.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim SIO 1 and switch it all on
Free to join · nothing to install to start · cancel anytime
Claim free → unlock everything

About SIO 1

What kind of vessel is SIO 1?
SIO 1 is a vessel flagged to United States of America.
What is SIO 1's MMSI?
SIO 1's MMSI is 367075040. Call sign WXD5803.
Is SIO 1 on the Master's Mate Safety Initiative Network?
Not yet. If SIO 1 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).

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