MMSI 366637560 · Call sign WCM4818
Not yet on Master's MateSONJA E flies the American flag — a boat. Officially she's MMSI 366637560, call sign WCM4818. The Master's Mate Safety Initiative Network welcomes SONJA E — free to join, cruiser-run, and always on watch.
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 SONJA E on the map. It hands you the full bridge:
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