Thank goodness all of the victims have been found and returned to their loved ones. May they rest in peace.
The local press (Phuket Gazette March 14, p 1) are reporting the weather conditions as a waterspout, though they do not attribute that determination to any official source. The descriptions given by survivors and the captain of the sunken boat do seem to support the theory that they were struck by a waterspout.
According to organisations such as the National Weather Service in the US, waterspouts are highly localized, severe weather events that are capable of capsising and sinking vessels of the size of this dive boat, "with maximum brief wind speeds of hurricane force or greater." If in fact the storm the boat got caught in did produce a spout, it is conceivable that this vessel might be struck full on while another nearby at the same time might simply have got buffeted and weathered the storm without incident. Yes, water spouts and severe thunderstorms are usual for this time of year in this part of the world; most of us who are out on the water regularly here have seen spouts as we motored back to Chalong. Fortunately, all sightings I have personally witnessed have been in the daytime and the captains were able to steer clear.
I don't think anyone would argue against an investigation, or that questions of the boat's seaworthiness--specifically center of gravity, ratio of beam to length, and draft when fuel and water tanks are empty--should be examined. We decidedly do need to learn from all catastrophes in order to enhance safety at sea. But until the answers to the many questions the accident has raised have been answered, I find it precipitous to be assigning blame to the shipyard, the naval architects, the dive operation, the captain, or whomever else. Raise questions, yes. But there's just not enough information yet to lay the responsibility for these deaths at any particular doorstep. More than likely it is some combination of many factors.