MMSI 366601840 · Call sign WCH9869
Not yet on Master's MateSEA YA is a vessel flagged in the United States. On AIS she appears as MMSI 366601840, call sign WCH9869. It's free to add SEA YA to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
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
Joining the Safety Initiative Network doesn't just put SEA YA on the map. It hands you the full bridge:
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