This paper evaluates the combination of a ducted rocket with a solid fuel ramjet to enhance the acceleration capabilities of the solid fuel ramjet cycle. Trade studies were conducted on both an air launched high speed cruise missile and a low altitude ground launched missile. Study results showed a greater than 20% reduction in total propellant (booster and ramjet) required using the combined ducted rocket cycle. The feasibility of the combined cycle was demonstrated in a test program. Testing evaluated both thrust and surface regression rates for solid fuel ramjet grains only and solid fuel grains augmented with ducted rocket flow. Test results showed 100% net thrust augmentation is achievable during ducted rocket burn with minimum effect on solid fuel ramjet grain burning characteristics after ducted rocket burn-out. Results of the paper clearly demonstrate the feasibility of the combined ducted rocket/solid fuel ramjet cycle for enhancing the acceleration capabilities of solid fuel ramjet powered missiles.