MMSI 366978770 · Call sign WDB9574
Not yet on Master's MateMadonna, a workboat wearing American colours, measures 15.9 metres on deck. She's built with a beam measuring 6.8 metres and a 2.5 m draft. Officially she's MMSI 366978770, call sign WDB9574. Madonna earns her keep on the water; the free Master's Mate Safety Initiative Network keeps a watching fleet and a distress mesh close at hand.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Joining the Safety Initiative Network doesn't just put Madonna on the map. It hands you the full bridge:
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