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)
R/V SEA EXPLORER
MMSI 366938380 · Call sign WCH9774
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
19.8 m
Beam
6.1 m
Draft
2.1 m
Call sign
WCH9774
Official No.
698503
AIS reports
1
On the American registry, R/V SEA EXPLORER is a 19.8-metre passenger craft. Her hull carries a 6.1-metre beam and a draft measuring 2.1 metres. Officially she's MMSI 366938380, call sign WCH9774. Join R/V SEA EXPLORER to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard R/V SEA EXPLORER 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 R/V SEA EXPLORER 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 R/V SEA EXPLORER 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 R/V SEA EXPLORER and switch it all on
Free to join · nothing to install to start · cancel anytime
About R/V SEA EXPLORER
What kind of vessel is R/V SEA EXPLORER?
R/V SEA EXPLORER is a Passenger (Inspected) flagged to United States of America.
What is R/V SEA EXPLORER's MMSI?
R/V SEA EXPLORER's MMSI is 366938380. Call sign WCH9774.
How big is R/V SEA EXPLORER?
R/V SEA EXPLORER is about 19.8 m long, 6.1 m on the beam, drawing 2.1 m.
Is R/V SEA EXPLORER on the Master's Mate Safety Initiative Network?
Not yet. If R/V SEA EXPLORER is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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