In 1628, the royal warship Vasa was launched. It was Sweden's most expensive naval vessel ever built, costing over 5% of GNP. On its maiden voyage, the ship sailed 1,400 yards in its own harbor, heeled over to the side, and then sank. One third of the 150 crew and officers were killed. An inquiry was convened to establish the cause of the disaster, with testimony taken from, among others, the ship's captain, its officers, the ship's designer, and those responsible for its construction. No one was found guilty of negligence. The question is "Why did the Vasa sink?" The answer lies in the state of knowledge about shipbuilding of the time, the continual changes requested by the king, who was fighting in the Baltic, and the resulting experimental nature of the design.