RedactedNarrative: Operator was sailing out of Bay when he observed smoke coming from the engine compartment of his vessel.  He stopped the vessel and attempted to contain and extinguish the fire without success after emptying 3 fire extinguishers.  All five passengers were forced to abandon the vessel and was picked up by a nearby good Samaritan vessel  No injuries.  Vessel sank.  No determination of the cause of fire has been make by the Fire Department agencies at this time.