The objectives of the DLR project Diabolo are to develop methods and processes for the design and performance assessment of next-generation fighter aircraft configurations. Diabolo is a German Federal Ministry of Defence (BMVg) basic funded research project within DLR research framework of Defence Technology. In Diabolo technology developments through the entire spectrum of manned and semi-autonomous configurations are considered. The main focus in Diabolo is the design of a generic Future Fighter Demonstrator (DLR-FFD) to capture technological gaps and to demonstrate the design and assessment capabilities of the methods and processes developed at DLR. The technology spectrum ranges from aerodynamics, structure and aeroelasticity, through control system design, the layout of a control concept and flight mechanics analysis, technologies and the design of a propulsion concept (DLR-FFE - Future Fighter Engine) and the determination of radar, infrared and acoustic signature properties. The tasks of the Institute of Aerodynamics and Flow Technology in Braunschweig and Göttingen are: