Airboat. airboat is a mixture of airplane and boat with the thrills of both. it’s a boat powered by an airplane-type propeller with above-the-water rudders that is. Airboat #400 a 13′ swamp boat driving an airplane-type propeller. designed for use with glen-l series 650 boat trailer plans. photographs. Propeller cage/shroud optimization of an airboat design, is based on the classic airboat concepts, so additional information from these modern alterations is.