The ability to carry air power anywhere in the world, and both launch those aircraft to flight speed and bring them to a stop over extremely short distances, has been essential to carriers' decades-long dominance of naval warfare. To help provide similar capabilities—minus the 90,000-ton carriers—to U.S. military units around the world, DARPA's SideArm research effort seeks to create a self-contained, portable apparatus able to horizontally launch and retrieve unmanned aerial systems (UASs) of up to 900 pounds.