The SHELS monolithic aluminum investment casting measures approximately 36" x 33" x 20" and weighs 110 lb. This structure was designed for minimum weight and maximum structural efficiency, and is considered a state of the art development item. Its size, configuration, complexity and stringent metallurgical and quality requirements combine to make this unit exceed conventional production investment casting capabilities.
NCI's proprietary processes enable the SHELS structure to become reality. The launcher is a "J"-shaped box beam monolithic structure, cantilevered from the orbiter's side-wall adapter beam. The launcher requires a very weight efficient structure with a compact profile. Standard aerospace fabrication processes, such as riveting and welding are impractical due to limited access of rivet tooling, assembly fixtures and TIG welding torches within the box structure. The aerospace casting provides essentially 100% structural joint efficiency and maximizes available payload space.
Alternate designs and aerospace fabrication and aerospace casting technologies were considered and eliminated as viable manufacturing processes. NCI's technologies and rapid pattern production have proven to be the most viable approach to producing the Launch / Structure aerospace casting for carrying and ejecting the 600 lb. spacecraft payload from the Orbiter's adapter beam.