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 (Uninspected)
Over Under
MMSI 366911920 · Call sign WDB5644
Not yet on Master's MateType
Passenger (Uninspected)
Flag
USALength
15.8 m
Beam
5.1 m
Draft
2.7 m
Call sign
WDB5644
Official No.
678738
Hull ID
BERS0553D485
AIS reports
1
Over Under is an American passenger boat — 15.8 metres overall. She's built with 5.1 metres in the beam and a 2.7 m draft. Officially she's MMSI 366911920, call sign WDB5644. It's free to add Over Under to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard Over Under 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 Over Under 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 Over Under 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 Over Under and switch it all on
Free to join · nothing to install to start · cancel anytime
About Over Under
What kind of vessel is Over Under?
Over Under is a Passenger (Uninspected) flagged to United States of America.
What is Over Under's MMSI?
Over Under's MMSI is 366911920. Call sign WDB5644.
How big is Over Under?
Over Under is about 15.8 m long, 5.1 m on the beam, drawing 2.7 m.
Is Over Under on the Master's Mate Safety Initiative Network?
Not yet. If Over Under is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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