MMSI 367536790 · Call sign WDG4461
Not yet on Master's MateWilliam Penn, a passenger boat flying the American flag, measures 8.8 metres on deck. She's built with a beam of 3 m and a 1.2 m draft. On AIS she shows as MMSI 367536790, call sign WDG4461. For a boat that carries people, William Penn can lean on the Master's Mate Safety Initiative Network — free distress alerting and a fleet that's paying attention.
Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.
Switch on the safety stack — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Joining the Safety Initiative Network doesn't just put William Penn on the map. It hands you the full bridge:
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