The game features a number of challenging modes where aircraft can be imported (using the Steam overlay) or designed from scratch in order to achieve the racing or combat objectives. A sandbox mode also allows testing of any aircraft. In the design mode, parts are attached together, including structural elements, wings, propulsion, landing gear, cockpits, and weapons. Most components can be reshaped and painted. The planes are flown in a bland island setting, with plenty of mountains to crash into. There is seemingly realistic physics involved in the game, and the relatively intuitive plane designer makes SimplePlanes an effective simulation with reduced complexity.