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.
Passenger (Inspected)
Sounder
MMSI 367489080 · Call sign WDF7878
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
13.1 m
Beam
3.8 m
Draft
1.3 m
Call sign
WDF7878
Official No.
1235029
Hull ID
NRB40010J011
AIS reports
1
Sounder is a passenger vessel flagged in the United States, 13.1 metres in length. She's built with a 3.8-metre beam and a 1.3 m draft. She broadcasts as MMSI 367489080, call sign WDF7878. Sounder can be part of the Master's Mate Safety Initiative Network at no cost — a community watch that never sleeps.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard Sounder safe.
Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.
Switch on the safety stack — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Sounder 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 passenger & charter operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Sounder on the map. It hands you the full bridge:
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
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 Sounder and switch it all on
Free to join · nothing to install to start · cancel anytime
About Sounder
What kind of vessel is Sounder?
Sounder is a Passenger (Inspected) flagged to United States of America.
What is Sounder's MMSI?
Sounder's MMSI is 367489080. Call sign WDF7878.
How big is Sounder?
Sounder is about 13.1 m long, 3.8 m on the beam, drawing 1.3 m.
Is Sounder on the Master's Mate Safety Initiative Network?
Not yet. If Sounder is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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