The demand for the Air Force's remotely piloted aircraft (RPAs) has exploded in the past few years. Even though the Air Force has increased its number of RPA units, it has been unable to keep up with this demand. This problem is exacerbated by an inability to fill the ranks of RPA units. The result is that RPA personnel work inordinately long hours, and the RPA mission is more demanding in terms of flying time than the typical traditionally manned aircraft mission.