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.
Commercial Fishing Vessel
Northern Defender
MMSI 366901360 · Call sign WDB4700
Not yet on Master's MateType
Commercial Fishing Vessel
Flag
USALength
40.9 m
Beam
9.8 m
Draft
4.2 m
Call sign
WDB4700
IMO
7934250
Official No.
610393
AIS reports
1
Northern Defender is a fishing vessel listed on the the United States registry, measuring 40.9 metres. She's built with a 9.8 m beam and a 4.2 m draft. Look for MMSI 366901360, call sign WDB4700, IMO 7934250. Claim Northern Defender free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.
Free forever · No credit card · for working captains
Know where the fleet is. Get Northern Defender home safe.
Live AIS traffic, weather you can plan around, engine & systems telemetry, and a distress mesh that reaches nearby boats.
Keep the fleet in sight — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Northern Defender 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 captains
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Northern Defender on the map. It hands you the full bridge:
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.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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 Northern Defender and switch it all on
Free to join · nothing to install to start · cancel anytime
About Northern Defender
What kind of vessel is Northern Defender?
Northern Defender is a Commercial Fishing Vessel flagged to United States of America.
What is Northern Defender's MMSI?
Northern Defender's MMSI is 366901360. Call sign WDB4700. IMO 7934250.
How big is Northern Defender?
Northern Defender is about 40.9 m long, 9.8 m on the beam, drawing 4.2 m.
Is Northern Defender on the Master's Mate Safety Initiative Network?
Not yet. If Northern Defender is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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