Solar array systems currently under development are focused on near-term missions with designs optimized for the 30-50 kW power range. However, NASA has a vital interest in developing much larger solar arrays (up to 1 MW of power) for Solar Electric Propulsion (SEP) missions. Scaling to this size will require fundamental changes in many aspects of the solar array system design as embodied by NASA's Compact Telescoping Array (CTA) reference configuration. To address this emerging need for larger scale practical solar array systems, and to evolve NASA's CTA design into a design that is practical to manufacture and flight qualify, Roccor proposes the mega-watt-class ROC-Array. The ROC-Array is a CTA-derivative design that yields improved packaged volume and deployed frequency through a tension-stiffened hierarchical structure. Exploiting structural hierarchy through the use of tension guy wire elements and next-generation deployable boom systems will afford an improved packaging efficiency, increased stiffness, and reduced mass. Performance enhancements will be achieved by replacing the solid wall telescoping mast in the CTA reference design with a deployable tension-stiffened boom structure.