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
WALTER ALFONSO
MMSI 367413940 · Call sign WDE9139
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
14 m
Beam
5.5 m
Draft
1.4 m
Call sign
WDE9139
Official No.
609023
AIS reports
1
WALTER ALFONSO, an American service vessel, measures 14 metres on deck. She carries a 5.5-metre beam and a 1.4 m draft. Look for MMSI 367413940, call sign WDE9139. It's free to add WALTER ALFONSO to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
Free forever · No credit card · for working boats
Built for boats that work — like WALTER ALFONSO.
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 WALTER ALFONSO 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 WALTER ALFONSO 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 WALTER ALFONSO and switch it all on
Free to join · nothing to install to start · cancel anytime
About WALTER ALFONSO
What kind of vessel is WALTER ALFONSO?
WALTER ALFONSO is a Offshore Supply Vessel flagged to United States of America.
What is WALTER ALFONSO's MMSI?
WALTER ALFONSO's MMSI is 367413940. Call sign WDE9139.
How big is WALTER ALFONSO?
WALTER ALFONSO is about 14 m long, 5.5 m on the beam, drawing 1.4 m.
Is WALTER ALFONSO on the Master's Mate Safety Initiative Network?
Not yet. If WALTER ALFONSO is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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