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.
Offshore Supply Vessel
Grouper
MMSI 366947770 · Call sign WDB7770
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
21.8 m
Beam
9.8 m
Draft
2.1 m
Call sign
WDB7770
IMO
7947661
Official No.
609642
AIS reports
1
Grouper flies the American flag — a 21.8-metre utility vessel. She's built with 9.8 metres in the beam and a 2.1-metre draft. She's on record as MMSI 366947770, call sign WDB7770, IMO 7947661. Grouper is invited to the free Master's Mate Safety Initiative Network, where cruisers keep each other safe.
Free forever · No credit card · for working boats
Built for boats that work — like Grouper.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Grouper 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 working boats
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Grouper on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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 Grouper and switch it all on
Free to join · nothing to install to start · cancel anytime
About Grouper
What kind of vessel is Grouper?
Grouper is a Offshore Supply Vessel flagged to United States of America.
What is Grouper's MMSI?
Grouper's MMSI is 366947770. Call sign WDB7770. IMO 7947661.
How big is Grouper?
Grouper is about 21.8 m long, 9.8 m on the beam, drawing 2.1 m.
Is Grouper on the Master's Mate Safety Initiative Network?
Not yet. If Grouper is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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