If a bloke is drunk he's said to be "Three sheets to the wind " I would imagine it's something to do with the Royal Navy and sailing ships .Anybody Know ? .
To add to Mtube's link...Since the sheets are the name for the ropes that control the sails, if the ends are let loose, and they are held out of reach of the crew by a strong wind, sailors would be left with with no way to control the sails. Presumably, the vessel's course could become other to that which was wanted.