altair industries driftboat plans altair offers complete plans and a construction guide for a 16′ mckenzie river drift boat. (added: 2-dec-2003 hits: 44766) my. We have power boat building designs of all types such as power cats, cruisers, and more. view jon boat deck plans & boat cabin plans for more details.. Welcome to spira international home-built boat plans. spira international offers a wide variety of different power, rowing, and sailing skiffs, dories, and other boat.