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
HARBOR MASTER
U.S. Official No. 583551
Not yet on Master's MateType
Towing Vessel
Flag
USALength
10.9 m
Beam
3.7 m
Draft
1.7 m
First reported
Jun 2026
AIS reports
1
HARBOR MASTER, an American working vessel, measures 10.9 metres on deck. Her hull carries a beam measuring 3.7 metres and a draft measuring 1.7 metres. On the registers she's U.S. official number 583551. Working vessels like HARBOR MASTER are never truly alone on the Master's Mate Safety Initiative Network — free, with a fleet on watch.
Free forever · No credit card · for working boats
Built for boats that work — like HARBOR MASTER.
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 HARBOR MASTER 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 HARBOR MASTER 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 HARBOR MASTER and switch it all on
Free to join · nothing to install to start · cancel anytime
About HARBOR MASTER
What kind of vessel is HARBOR MASTER?
HARBOR MASTER is a Towing Vessel flagged to United States of America.
What is HARBOR MASTER's U.S. Official No.?
HARBOR MASTER's U.S. Official No. is 583551.
How big is HARBOR MASTER?
HARBOR MASTER is about 10.9 m long, 3.7 m on the beam, drawing 1.7 m.
Is HARBOR MASTER on the Master's Mate Safety Initiative Network?
Not yet. If HARBOR MASTER is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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