A light-sport aircraft, also known as light sport aircraft or LSA, is a small aircraft that is simple to fly and that meets certain regulations set by a national aviation authority restricting weight and performance. For example, in Australia the Civil Aviation Safety Authority defines a light-sport aircraft as a heavier-than-air or lighter-than-air craft, other than a helicopter, with a maximum gross takeoff weight of not more than for lighter-than-air craft; for heavier-than-air craft not intended for operation on water; or for aircraft intended for operation on water. It must have a maximum stall speed of in landing configuration; a maximum of two seats; there is no limit on maximum speed unless it is a glider, which is limited to Vne 135 kn CAS; fixed undercarriage (except for amphibious aircraft, which may have repositionable gear, and gliders, which may have retractable gear); an unpressurized cabin; and a single non-turbine engine driving a propeller if it is a powered aircraft.