In-between 2000 and 2007 the Swedish armed forces helicopter wing experienced several major aviation accidents. These accidents were remarkable with regards to the facts that aviation accidents had been decreasing in numbers since 1970; that safety technology had developed; and that findings in earlier research suggests that the characteristics of Swedish national culture should lower the risk of accidents. The purpose of this study is to contribute to the understanding of these aviation accidents by applying theories of organizational factors in aviation accidents and organizational learning. The chosen method is a single case study conducted with a qualitative approach, focusing on the helicopter wing, its squadrons, structure and its command. The results of this study show that aviation accidents could be the result of many contributory organizational factors. They also show that organizational learning should be an integrated part of risk management. Finally they show that reorganizations considerably reduces an organizations capability to manage risks. The conclusion is that when safety critical organizations such as the military reorganize, they tend to lose critical procedures, objectives, management and structure which leads to higher risks and in some cases to accidents.