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
Northstar 4
MMSI 368006440 · Call sign WDJ7412
Not yet on Master's MateType
Towing Vessel
Flag
USALength
13.9 m
Beam
4.5 m
Draft
1.3 m
Call sign
WDJ7412
Official No.
560915
AIS reports
1
Northstar 4 is an utility vessel registered in the United States, 13.9 metres overall. She carries a 4.5-metre beam and a 1.3-metre draft. She's listed under MMSI 368006440, call sign WDJ7412. Northstar 4 earns her keep on the water; the free Master's Mate Safety Initiative Network keeps a watching fleet and a distress mesh close at hand.
Free forever · No credit card · for working boats
Built for boats that work — like Northstar 4.
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 Northstar 4 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 Northstar 4 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 Northstar 4 and switch it all on
Free to join · nothing to install to start · cancel anytime
About Northstar 4
What kind of vessel is Northstar 4?
Northstar 4 is a Towing Vessel flagged to United States of America.
What is Northstar 4's MMSI?
Northstar 4's MMSI is 368006440. Call sign WDJ7412.
How big is Northstar 4?
Northstar 4 is about 13.9 m long, 4.5 m on the beam, drawing 1.3 m.
Is Northstar 4 on the Master's Mate Safety Initiative Network?
Not yet. If Northstar 4 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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