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)
h2o below
MMSI 366898210 · Call sign WDB4417
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
11 m
Beam
4.3 m
Draft
1.8 m
Call sign
WDB4417
Official No.
1136903
AIS reports
1
Registered in the United States, h2o below is an 11-metre ferry. She's built with a beam of 4.3 m and a 1.8-metre draft. Her papers read MMSI 366898210, call sign WDB4417. For a boat that carries people, h2o below can lean on the Master's Mate Safety Initiative Network — free distress alerting and a fleet that's paying attention.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard h2o below 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 h2o below 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 h2o below 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 h2o below and switch it all on
Free to join · nothing to install to start · cancel anytime
About h2o below
What kind of vessel is h2o below?
h2o below is a Passenger (Inspected) flagged to United States of America.
What is h2o below's MMSI?
h2o below's MMSI is 366898210. Call sign WDB4417.
How big is h2o below?
h2o below is about 11 m long, 4.3 m on the beam, drawing 1.8 m.
Is h2o below on the Master's Mate Safety Initiative Network?
Not yet. If h2o below is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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