RedactedNarrative: The vessel was traveling in a northeasterly direction in the Gulf of Mexico in open water.  The vessel struck an unknown submerged object , floating at the surface, believed to be a log.  The vessel began taking on water.  The vessel flooded and capsized.  The occupants donned their personal floatation devices as the vessel flooded.  They entered the water and stayed with the capsized vessel until help arrived.