The first attempts to perform a Moon landing took place in 1962 during the Rangers 3, 4 and 5 missions flown by the United States. All three Block II missions basic vehicles were 3.1 m high and consisted of a lunar capsule covered with a balsa wood impact-limiter, 650 mm in diameter, a mono-propellant mid-course motor, a retrorocket with a thrust of , and a gold- and chrome-plated hexagonal base 1.5 m in diameter. This lander (code-named "Tonto") was designed to provide impact cushioning using an exterior blanket of crushable balsa wood and an interior filled with incompressible liquid freon. A 42 kg (56 pounds) metal payload sphere floated and was free to rotate in a liquid freon reservoir contained in the landing sphere.