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)
Expeditions four
MMSI 366911740 · Call sign WDP3945
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
19.8 m
Beam
7.2 m
Draft
1.7 m
Call sign
WDP3945
Official No.
1149135
AIS reports
2
Expeditions four is an American 19.8-metre passenger boat. Expeditions four has 7.2 metres in the beam and a 1.7 m draft. On AIS she shows as MMSI 366911740, call sign WDP3945. Expeditions four is welcome on the Master's Mate Safety Initiative Network — a free, community-run watch where boats look out for one another.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard Expeditions four 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 Expeditions four 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 Expeditions four 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 Expeditions four and switch it all on
Free to join · nothing to install to start · cancel anytime
About Expeditions four
What kind of vessel is Expeditions four?
Expeditions four is a Passenger (Inspected) flagged to United States of America.
What is Expeditions four's MMSI?
Expeditions four's MMSI is 366911740. Call sign WDP3945.
How big is Expeditions four?
Expeditions four is about 19.8 m long, 7.2 m on the beam, drawing 1.7 m.
Is Expeditions four on the Master's Mate Safety Initiative Network?
Not yet. If Expeditions four is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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