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
Otter
MMSI 338303000 · Call sign WDL3726
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
82 m
Beam
18.9 m
Draft
7.3 m
Call sign
WDL3726
IMO
9693525
Official No.
1260645
AIS reports
3
Registered in the United States, Otter is an 82-metre service vessel. She carries 18.9 metres in the beam and a 7.3 m draft. Officially she's MMSI 338303000, call sign WDL3726, IMO 9693525. The Master's Mate Safety Initiative Network welcomes Otter — free to join, cruiser-run, and always on watch.
Free forever · No credit card · for working boats
Built for boats that work — like Otter.
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 Otter 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 Otter 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 Otter and switch it all on
Free to join · nothing to install to start · cancel anytime
About Otter
What kind of vessel is Otter?
Otter is a Offshore Supply Vessel flagged to United States of America.
What is Otter's MMSI?
Otter's MMSI is 338303000. Call sign WDL3726. IMO 9693525.
How big is Otter?
Otter is about 82 m long, 18.9 m on the beam, drawing 7.3 m.
Is Otter on the Master's Mate Safety Initiative Network?
Not yet. If Otter is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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