In October 1998, NASA awarded the Small Expendable Launch Vehicle Services (SELVS) contract to Coleman Aerospace to provide launch services for NASA and NASA-sponsored small payloads. Coleman was one of two contractors competing for individual task orders under SELVS. The small-class payloads to be launched would support the goals of NASA’s Earth Science and Space Science enterprises.The SELVS contract had a five year period of performance that ended October 2003.
Coleman was awarded a task order under the SELVS contract in June 2000 to develop a concept for NASA’s Alternate Access to Station (AAS) initiative. As part of this program, a launch vehicle had to be capable of launch with short notice to deliver critical supplies to the International Space Station and to retrieve waste. Coleman offers NASA conventional approaches using ordinary ground-launched solid rocket configurations, plus a highly innovative air-launch approach.
With the Coleman air-launch approach, small payloads can be placed in low-Earth orbit quickly. In this scenario, a parachute system extracts a solid-booster launch vehicle from a flying cargo aircraft. The rocket uses global positioning system/inertial navigation system (GPS/INS) guidance. After separating from the parachute extraction system, the first-stage motor is ignited, and the rocket flies its mission to orbit.
The Coleman air-launch approach offers many advantages, including the ability to launch the payload from any inclination required—the airplane simply flies to that inclination. The aircraft also effectively acts as the first stage of the system, delivering the launch vehicle high in the atmosphere to an altitude of 15,000 to 20,000 feet before the first rocket stage is ignited. The system can be launched rapidly because the launch vehicle is integrated and launched horizontally and need not be stacked on a ground launch pad. |
