In this clip, rocket power plants made by Aerojet are tested on a plane that takes off.Valves are checked, then a high pressure air line is connected to the plant. The valves are closed again, then the plants are inspected on the plane. Valves are opened on the rockets, and the main engines are started (a propellor spins). The plane taxis to the runway, then the rockets fire up. The rocket powered plane takes off, smoke billowing from the exhaust. Next is a shot of hands showing photographs of various planes that will also be rocket powered.