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.
Recreational
Four Across
MMSI 366937730 · Call sign WDB7177
Not yet on Master's MateType
Recreational
Flag
USALength
15.2 m
Beam
4.9 m
Draft
3.7 m
Call sign
WDB7177
Official No.
1128120
AIS reports
1
Registered in the United States, Four Across is a 15.2-metre private cruiser. Her hull carries a beam measuring 4.9 metres and a draft of 3.7 m. Officially she's MMSI 366937730, call sign WDB7177. Claim Four Across free and let the Master's Mate Safety Initiative Network keep an eye on her, on the water or off.
Free forever · No credit card · for recreational captains
Keep Four Across looked after — even when you’re not aboard.
Anchor alarms that wake you, a live camera at the dock, and weather you can trust before every run.
Look after her — claim free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Four Across 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 recreational captains
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Four Across on the map. It hands you the full bridge:
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim Four Across and switch it all on
Free to join · nothing to install to start · cancel anytime
About Four Across
What kind of vessel is Four Across?
Four Across is a Recreational flagged to United States of America.
What is Four Across's MMSI?
Four Across's MMSI is 366937730. Call sign WDB7177.
How big is Four Across?
Four Across is about 15.2 m long, 4.9 m on the beam, drawing 3.7 m.
Is Four Across on the Master's Mate Safety Initiative Network?
Not yet. If Four Across is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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