MoTV

American space tug. Study 2003. SpaceDev design for a low-cost, restartable hybrid propulsion space tug or upper stage.

The MoTV was the SpaceDev Maneuvering and orbital Transfer Vehicle. It used a hybrid motor based on HTPB for fuel and N2O (nitrous oxide) as an oxidizer. Features included: Total impulse could be controlled by burn length (significant advantage over solids); oxidizer could be used for cold-gas attitude thrusters (for steering); could be used for multiple burns. These features made it an excellent candidate for complex orbital operations at a much lower cost than a similar liquid system. Two hybrid propulsion systems were designed and built by SpaceDev for Scaled Composites and the Air Force.

The NRO awarded SpaceDev four separate competitive contracts totaling $1.5 million for hybrid rocket engine design and development. These contracts related to SpaceDev advanced hybrid rocket applications and its orbital transfer vehicle development. Under the NRO contracts and a $105,000 award from the California Space & Technology Alliance (CSTA), SpaceDev performed a number of hybrid motor and MoTV test firings beginning in November 2000. SpaceDev also developed specific mission and utility analyses to support NRO objectives. SpaceDev built and test fired a prototype version of its Maneuvering and orbital Transfer Vehicle (MoTV).