In this preliminary study, a general plan for the evaluation of the noise and gas emissions produced by military flights and the study of different means to reduce this annoyance is proposed by FOI´s department of aviation environmental research. First the importance given to the reduction of the environmental impact of the Swedish defense materiel as well as the Swedish experience in solving environmental issues and its international recognition is presented. A special emphasis is given to the mission given by the Swedish government to the Swedish Defence Materiel administration to reduce the environmental impact of military air traffic. The experience and the different tools at the disposition of FOI to compute aircraft noise and gas emission are then presented in details. A particular emphasis is given on the experience acquired by FOI with civil aviation and on the possibilities to put this knowledge at the disposal of the Swedish Defence Materiel administration. Finally a project proposal is presented. The goal of the project would be to reduce, in the long run, some of the environmental pollutions generated by the activities of the Swedish Air Force. At this stage of the project, it is impossible to have a complete view over the situation. This report should therefore be seen as a preliminary proposal open to comments and suggestions.