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
True Blue
Offshore Supply Vessel · United States of America · MMSI 338443000 · Call sign WDN7309
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
73.2 m
Beam
17.1 m
Draft
6.4 m
Call sign
WDN7309
IMO
9211561
Official No.
1077920
AIS reports
6
True Blue is an American working craft — 73.2 metres overall. Below, she has a 17.1-metre beam and a draft of 6.4 m. Officially she's MMSI 338443000, call sign WDN7309, IMO 9211561. True Blue is welcome on the Master's Mate Safety Initiative Network — a free, community-run watch where boats look out for one another.
Free forever · No credit card · for working boats
Built for boats that work — like True Blue.
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 True Blue 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 True Blue 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 True Blue and switch it all on
Free to join · nothing to install to start · cancel anytime
About True Blue
What kind of vessel is True Blue?
True Blue is a Offshore Supply Vessel flagged to United States of America.
What is True Blue's MMSI?
True Blue's MMSI is 338443000. Call sign WDN7309. IMO 9211561.
How big is True Blue?
True Blue is about 73.2 m long, 17.1 m on the beam, drawing 6.4 m.
Is True Blue on the Master's Mate Safety Initiative Network?
Not yet. If True Blue is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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