The aim of SEFA is to develop technology design criteria (sound engineering) based on a thorough assessment of which characteristics would make aircraft more acceptable for airport communities from noise signature standpoint (spectral and directivity shapes, impact of separation time), addressing from a complementary perspective the concerns of close communities (peak periods of activities with short separation time), distant ones (high altitude traffic with low background noise) and disturbance from night operations. As of now, such criteria do not exist and so far, aircraft noise engineering has focused on achieving ever-lower noise levels for individual events and at close distance from the runway. The project objectives are consistent with the Sixth Framework Programme on Aeronautics and Space, promoting open upstream research for reduction of noise at source as well as improved understanding of the impact of aircraft noise in the community. Thanks to its technical scope and work plan, SEFA is aimed at addressing both aspects and has the ambitious goal of improving the relationship between the technology optimisation processes and how the resulting aircraft sound misperceived. Through improved optimisation of noise reduction concepts, SEFA will have a significant strategic impact in reinforcing the competitiveness of the European industry while addressing the long-term vision 2020 environmental goals. A novel approach, based on sound quality engineering practices, will be used to define optimum aircraft community noise shapes. Psychometric testing for aircraft sound optimisation will validate these targets. To support the definition of design criteria able to meet these target sounds, innovative simulation tools (virtual aircraft and virtual resident) will be developed to allow the identification of relevant physical parameters which impact the noise that can be heard at the resident location.