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
Herring
MMSI 366947780 · Call sign WDB7771
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
21.8 m
Beam
9.8 m
Draft
2.1 m
Call sign
WDB7771
IMO
7948421
Official No.
614063
AIS reports
1
Herring is a harbour workboat registered in the United States, 21.8 metres long. Her hull carries a 9.8 m beam and a draft of 2.1 m. Officially she's MMSI 366947780, call sign WDB7771, IMO 7948421. Join Herring to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.
Free forever · No credit card · for working boats
Built for boats that work — like Herring.
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 Herring 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 Herring 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 Herring and switch it all on
Free to join · nothing to install to start · cancel anytime
About Herring
What kind of vessel is Herring?
Herring is a Offshore Supply Vessel flagged to United States of America.
What is Herring's MMSI?
Herring's MMSI is 366947780. Call sign WDB7771. IMO 7948421.
How big is Herring?
Herring is about 21.8 m long, 9.8 m on the beam, drawing 2.1 m.
Is Herring on the Master's Mate Safety Initiative Network?
Not yet. If Herring is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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