Jointly organised by the European Commission and the Centre for the Development of Industrial Technology in Spain (CDTI), the Aeronautics Days sixth edition - 'Aerodays 2011' - was held on 30th - 31st March and 1st April 2011 in the Palacio Municipal de Congresos of Madrid. It brought together 1400 delegates - policy makers, aerospace manufacturers, engineers, researchers and customers - to report and discuss the challenges and solutions for creating greener, safer, secure and competitive solutions for aeronautics and air transport in Europe. Highlights included 'Flightpath 2050', Europe's vision for future aviation. The present book, published by the European Commission, brings together about 80 papers selected by a Scientific Advisory Committee with the intention to make broadly known the main themes and issues addressed on the occasion of this Convention. Given the strategic importance of the latter, these post-conference proceedings constitute a reference document providing an overview on aeronautical research within Europe more particularly devoted to Commission supported programmes and networks.