UNSC Aerospace Force

The UNSC Aerospace Force (UNSCAF), sometimes known as the Air Force for short, is one of four military branches of the United Nations Space Command. The Aerospace Force's responsibilities are traditionally defined as extending throughout a world's Hill sphere, though most of their assets are atmospheric. Although their role overlaps somewhat with the UNSC Navy in orbital zones, the Navy is defined as a mobile, expeditionary force, whereas the Aerospace Force's focus is more localized.

The Aerospace Force maintains extensive fleets of planetary defense assets, including launch facilities, aerial and orbital fighter craft, small warships such as cutters and corvettes, as well as orbital defense platforms. They also operate maritime-based launch platforms. The Aerospace Force provides transportation and support for the UNSC Army and the two share many of their facilities. In peacetime, the Aerospace Force is responsible for orbital surveillance, asteroid defense, customs policing, space traffic control, as well as search and rescue. They also maintain infantry units, including EVA-specialized boarding parties and high-altitude insertion special forces.