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.
Towing Vessel
Sierra Dawn
MMSI 366984980 · Call sign WDB9913
Not yet on Master's MateType
Towing Vessel
Flag
USALength
46.2 m
Beam
12.2 m
Draft
2.7 m
Call sign
WDB9913
Official No.
522413
AIS reports
1
Registered in the United States, Sierra Dawn is a 46.2-metre working vessel. Her hull carries a 12.2 m beam and a draft measuring 2.7 metres. Find her under MMSI 366984980, call sign WDB9913. Sierra Dawn can join the Master's Mate Safety Initiative Network for free: think of it as a watch network that has every boat's back.
Free forever · No credit card · for working boats
Built for boats that work — like Sierra Dawn.
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 Sierra Dawn 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 Sierra Dawn 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 Sierra Dawn and switch it all on
Free to join · nothing to install to start · cancel anytime
About Sierra Dawn
What kind of vessel is Sierra Dawn?
Sierra Dawn is a Towing Vessel flagged to United States of America.
What is Sierra Dawn's MMSI?
Sierra Dawn's MMSI is 366984980. Call sign WDB9913.
How big is Sierra Dawn?
Sierra Dawn is about 46.2 m long, 12.2 m on the beam, drawing 2.7 m.
Is Sierra Dawn on the Master's Mate Safety Initiative Network?
Not yet. If Sierra Dawn is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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