COSMA - Community Orientated Solutions to Minimize Aircraft Noise Annoyance - was a European approach within the 7th Framework Programme of the European Commission. Aircraft noise engineering is focused more or less on the reduction of the noise emission for single aircraft components, and separately treating the noise abatement procedures during take-off and landing. COSMA’s aim was to combine both under the aspect of noise annoyance: To develop basic engineering criteria for an annoyance friendly aircraft design and managing flight operation routines in order to reduce the noise related annoyance within airport communities. The project had to create the link between the aircraft/sound engineering domain, and the noise effects domain. To achieve this goal, extensive field studies around European airports, combined with psychometric studies in laboratories have built the basis for describing the optimal aircraft sound characteristics which anticipates a lower annoyance. Specific sound synthesis methods, combined with the optimization of procedures for flight operations were used to create low noise annoyance practices, including future aircraft concepts. The authors give an overview about the final status of the project’s achievements in the major project areas: Annoyance related examinations, sound engineering, and optimization.