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.
Vessel
Big Thunder
MMSI 368250020 · Call sign WDM9149
Not yet on Master's MateFlag
USACall sign
WDM9149
Official No.
640135
AIS reports
1
Big Thunder is an American vessel. She's listed under MMSI 368250020, call sign WDM9149. Big Thunder can join the Master's Mate Safety Initiative Network for free: think of it as a watch network that has every boat's back.
Free forever · No credit card
Is Big Thunder your boat?
Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.
Claim this boat — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever Big Thunder 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
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Big Thunder 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.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
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.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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 Big Thunder and switch it all on
Free to join · nothing to install to start · cancel anytime
About Big Thunder
What kind of vessel is Big Thunder?
Big Thunder is a vessel flagged to United States of America.
What is Big Thunder's MMSI?
Big Thunder's MMSI is 368250020. Call sign WDM9149.
Is Big Thunder on the Master's Mate Safety Initiative Network?
Not yet. If Big Thunder is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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