This research deals with the new requests made to Aeronautics social workers. Addressing, in particular, the impacts to the social work, considering the relationship between the transformations that have been made in the universe of military work and defense policies of Brazil, approved in the 2000s. It sought to give visibility to the answers, built by the profession, from a point not yet analyzed, which is related to the work of social workers in the operational missions of the Armed Forces. The work started with a bibliographical review on the current national defense policies, and especially those of a subsidiary nature, as well as the examination of the main technical norms that regulate the professional performance. To make this study viable, a qualitative research was carried out, aiming to analyze the professional work of social workers and the requisitions of the operational field. In this way, three axes were used, namely: Military workers and the challenges of the subsidiary operational field; Subsidiary Missions: the look of Social Service and the construction of its place; Social Service and the legitimation of the socio-occupational space in the missions of the Brazilian Air Force, involving military organizations of the Aeronautics Command in the areas of social assistance, health, airspace control, operational logistics and aviation, throughout the country. The results of the research demonstrate that the scenario of intense transformations and new requisitions for the profession, in the Aeronautics, is accompanied by a work condition, in most cases, marked by the instability character in the military service. Another signaled point focuses on the impacts to the profession, originating, on the one hand, by the ongoing transformations in the world of work and, on the other hand, the new requisitions that accompany current national defense policies. The results of the research also indicate the punctual and fragmented nature of social work actions within the scope of subsidiary missions. This issue is justified by the normative logic itself, which provides for transitoriness in military operations of this nature, since this is not the constitutional mission of the Armed Forces. Based on the data collected, this thesis argues the need for the profession to know about national defense policies and, in particular, the current use of subsidiary missions, considering that the invisibility of this area makes it difficult to invest in studies on the socio-occupational space of the Armed Forces, besides maintaining the distance between the actions and possibilities of this field with the ethical-political project of the Social Work.