Vice Admiral Thavatorn Thinsuwan, Commander of Royal Thai Navy 3, said today he was puzzled why the Navy's assistance was not sought until 24 hours after the disappearance of Carmel Brookes, 60.
Ms Brookes set sail from Langkawi to Phuket with her partner, Dr Gerald Goeden, on January 23. Dr Goeden later told officials that Ms Brookes appeared to have fallen overboard somewhere between Trang and Koh Lanta, according to a friend.
Officers at the Sea Rescue Centre in Krabi told Phuketwan that they had been informed the sailing trip was a holiday break from Dr Goeden's work on reef research in Langkawi.
Friends and relatives of Ms Brookes have been told that the pair were taking turns at the helm of the yacht, Moondancer.
Michelle Black, a friend of Ms Brookes, later wrote: ''When his [Dr Goeden's] alarm went off, signalling it was time for him to take over, he went up on deck.
''But she wasn't there. Apparently she had a sailing safety harness on, but it had been unattached from the boat.''
According to officials at the Krabi Rescue Centre, the pair had been drinking before Dr Goeden turned in, police in Krabi were told.
The officials are puzzled as to why the pair were taking turns at the helm when they were on a relaxing holiday.
''Most yachties tend to anchor for the night on trips between Langkawi and Phuket,'' one official said.
Although the weather is usually mild in the Andaman Sea at this time of year, there can be squalls and strong breezes.
Do Goeden told police that he searched on Moondancer for Ms Brookes for several days before making to land.
He had set off an emergency signal when he discovered Ms Brookes was missing, her relatives were told. The signal was picked up in Australia.
Vice Admiral Thavatorn said today that officials and vessels in the region were now on the lookout for Ms Brookes' body.
He said the lessons were that alcohol is best not consumed on yachts while at sea, and that life jackets should be warn for safety at all times.