There are three primary attributes to unmanned systems compared with piloted aircraft (aside from not having to pay crew salaries and benefit packages). First, an unmanned aircraft is not limited by the sensitivity to G-forces of the human pilot. Admittedly, this is mostly a concern for combat aircraft. Second, unmanned aircraft can complete missions that would be too risky for human-powered aircraft (this could involve combat, but also police pursuit of suspects, search and rescue in bad weather, firefighting and inspection of hazardous-materials spills or nuclear meltdowns, for example). And finally, there are some missions that are just so simplistic and repetitive that even the most astute human would eventually become too bored to be able to remain effective (think long-term border patrol or a police stakeout, for example). Some drone platforms that are perfectly suited for these missions are capable of remaining aloft for days at a time. The physiological limitations of a human crew (sleep, food, etc.) would not permit full use of the aircraft’s capabilities. The extra 200 pounds (or more) of fuel or payload doesn’t hurt, either.