Rocket engine bipropellant valve problems and current efforts

In developing the highly successful bipropellant valves for the Apollo primary propulsion engines, a variety of developmental problems were encountered and resolved. These problems and the new technology that is being pursued to eliminate or minimize these problems on the space shuttle orbital maneuvering engine are discussed. The space shuttle, being a reusable system, has new requirements of the valve. The potential effects of these requirements on valve design and potential solutions are also discussed.