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ACFA 2020 (active control for flexible aircraft) is a collaborative research project funded by the European Commission under the seventh research framework programme. The project deals with innovative active control concepts for 2020 aircraft configurations like the blended wing body (BWB) aircraft. The main objectives of ACFA are the design of a new ultra efficient 450 passenger BWB type aircraft as well as the provision of robust adaptive multichannel control architectures for such aircraft. The objective of the newly designed controllers is an ambitious improvement of ride comfort and handling qualities, as well as load reduction on BWB type aircraft. Based on the attained load reduction, the structure of the 450-passenger aircraft can be resized with the goal of an ambitious weight saving for further improvement of fuel efficiency. Active control requirements influence the design process of control surfaces and overall aircraft design, respectively. Hence, the conventional aircraft design process had to be adapted to the new requirements. The aircraft design framework described in this article has proven its efficiency in the development of the ACFA BWB aircraft. Within a time period of 1 year, an airframe has been developed under the constraints of multiple domain requirements. This article presents the process and the results of the design activities of the BWB aircraft, which form the basis for a detailed concept analysis as well as the investigation of multiple-input multipleoutput control architectures.

This paper describes the con¦guration selection process in the FP7 project ACFA (Active Control for Flexible Aircraft) 2020 in view of the Advisory Council for Aeronautics Research in Europe (ACARE) aims. The design process challenges and the comparison of a blended wing body (BWB) aircraft with a wide body carry-through wing box (CWB) con¦guration are described in detail. Furthermore, the interactions between the conceptual design and structural design using multidisciplinary design optimization (MDO) to rapidly generate and adapt structural models to design changes and provide early feedback of mass and center of gravity values for these nontraditional con¦gurations are discussed. Comparison of the two concepts determined that the developed all-lifting BWB airframe has the potential for a signi¦cant reduced fuel consumption compared to the CWB.

Die Rohrfachwerk‐Verbundbrücke Korntal‐Münchingen wird als Beispiel für den modernen Brückenbau in Deutschland vorgestellt, bei dem durch werkstoffübergreifendes Ingenieurdenken innerhalb der Straßenbauverwaltungen, Planungsbüros und Baufirmen innovative Lösungen möglich werden.Der erste Teil des Aufsatzes befaßt sich mit dem Entwurf, im zweiten Teil werden Ausschreibung, Vergabe und Bauausführung behandelt.