Distributed Propulsion: New Opportunities for an Old Concept

Abstract : Distributed propulsion can be broadly defined as distributing the airflows and forces generated by the propulsion system about an aircraft in such a way as to improve the vehicle's aerodynamics, propulsive efficiency, structural efficiency, and aeroelasticity. The confluence of several synergistic factors with recent technical developments suggests distributed propulsion may now yield both new capabilities and new economics for military flight vehicles. Over a 12 month period, this study explored the potential for distributed propulsion combined with pneumatic aerodynamics and flow control to enable new capabilities and new economics for military air vehicles. Aircraft and gas turbine designs focused on an ESTOL application (100m takeoff run, for a nominally C-27 size aircraft). Study outputs include: a quantification of distributed propulsion benefits such as enabling new mission capabilities and improving performance, reliability, and cost; a conceptual design of a distributed propulsion air vehicle; a conceptual design of small engines optimized for distributed propulsion; and delineation of the technical barriers that must be overcome to realize distributed propulsion aircraft, and candidate plans for overcoming such barriers.