Investigation into the impact of agility on conceptual fighter design

The Agility Design Study was performed by the Boeing Defense and Space Group for the NASA Langley Research Center. The objective of the study was to assess the impact of agility requirements on new fighter configurations. Global trade issues investigated were the level of agility, the mission role of the aircraft (air-to-ground, multi-role, or air-to-air), and whether the customer is Air force, Navy, or joint service. Mission profiles and design objectives were supplied by NASA. An extensive technology assessment was conducted to establish the available technologies to industry for the aircraft. Conceptual level methodology is presented to assess the five NASA-supplied agility metrics. Twelve configurations were developed to address the global trade issues. Three-view drawings, inboard profiles, and performance estimates were made and are included in the report. A critical assessment and lessons learned from the study are also presented

Multiple-Purpose Subsonic Naval Aircraft (MPSNA): Multiple Application Propfan Study (MAPS)

Study requirements, assumptions and guidelines were identified regarding carrier suitability, aircraft missions, technology availability, and propulsion considerations. Conceptual designs were executed for two missions, a full multimission aircraft and a minimum mission aircraft using three different propulsion systems, the UnDucted Fan (UDF), the Propfan and an advanced Turbofan. Detailed aircraft optimization was completed on those configurations yielding gross weight performance and carrier spot factors. Propfan STOVL conceptual designs were exercised also to show the effects of STOVL on gross weight, spot factor and cost. An advanced technology research plan was generated to identify additional investigation opportunities from an airframe contractors standpoint. Life cycle cost analysis was accomplished yielding a comparison of the UDF and propfan configurations against each other as well as against a turbofan with equivalent state of the art turbo-machinery

Model Scale and "Real" Flight of Generic UCAV and Advanced Combat Aircraft - An Industrial Perspective

An industrial view on experimental and numerical investigations related to advanced combat aircraft needs is given. A critical comparison in between experimental and numerical results under wind tunnel conditions and real flight numerical simulations is presented. The Reynolds and Mach number influence on the aerodynamic behavior together with the development of the complex flowfields around generic UCAV configurations at transonic speed, medium and high angles of attack conditions is discussed. Static CFD results of forces and moments as well as the flow structure of the longitudinal and lateral flow conditions are compared to wind-tunnel measurements. Here combat aircraft and flying-wing type UCAV flow-phenomena of such as separation emerging at round and sharp leading edges into interacting vortex flows are shown. Also their possible development at transonic conditions causing interacting shock-systems are addressed. While wind-tunnel (low) Reynolds number, subsonic conditions are thought economic, they may be far off flight (high) Reynolds number and realistic subsonic and transonic Mach number speeds. Therefore also free-flight, full-scale conditions have been prepared to probe the possible differences with the experimental and numerical investigations of the design and early development process of future shapes. This will show the sensitivity and possible basic uncertainty of the stability & control investigations of modern combat aircraft due to insufficient full-scale, free-flight knowledge