In a report released today, the board says the Marie J was attempting to return to McEachern's Point harbour in Tabusintac Bay on May 18, 2013, when it became grounded on the sandbar and water started spilling onto the deck.
The board says the boat was grounded for about 20 minutes before crashing waves pushed the vessel over the sandbar and into deeper water, where it sank.
None of the three men on board was wearing a life-jacket.
The board says that was common practice for fishermen in the area.
The body of a 23-year-old man was found hours later, while the bodies of a 35-year-old man and a 32-year-old man were found the following day.
It is unclear why the boat made a wide turn around the buoy but the board says weather conditions, limited visibility and the master's lack of experience with the recently leased vessel are all possibilities.
The board also says the accuracy of the position of the buoys and the sandbar were difficult to determine because of shifting and silting.