Editing Thrust vectoring (section)

====Exhaust vanes====
[[File:Antwerp V-2.jpg|thumb|Graphite exhaust vanes on a V-2 rocket engine's nozzle]]One of the earliest methods of thrust vectoring in rocket engines was to place vanes in the engine's exhaust stream. These exhaust vanes or jet vanes allow the thrust to be deflected without moving any parts of the engine, but reduce the rocket's efficiency. They have the benefit of allowing roll control with only a single engine, which nozzle gimbaling does not. The [[V-2 rocket|V-2]] used graphite exhaust vanes and aerodynamic vanes, as did the [[PGM-11 Redstone|Redstone]], derived from the V-2. The Sapphire and Nexo rockets of the amateur group [[Copenhagen Suborbitals]] provide a modern example of jet vanes. Jet vanes must be made of a refractory material or actively cooled to prevent them from melting. Sapphire used solid copper vanes for copper's high heat capacity and thermal conductivity, and Nexo used graphite for its high melting point, but unless actively cooled, jet vanes will undergo significant erosion. This, combined with jet vanes' inefficiency, mostly precludes their use in new rockets.