High Quality Content by WIKIPEDIA articles! An inflatable boat is a lightweight boat constructed with its sides and bow made of flexible tubes containing pressurised gas. For smaller boats, the floor and hull beneath it is often flexible. On boats longer than 3 metres (9.8 ft), the floor often consists of three to five rigid plywood or aluminium sheets fixed between the tubes but not joined rigidly together. Often the transom is rigid, providing a location and structure for mounting an outboard motor.