Imagine having a stealthy military aircraft capable of flying over enemy territory, ready to strike and destroy surprise threats immediately without any risk to American pilots. Two Boeing Joint Unmanned Combat Air Systems' (J-UCAS) X-45A unmanned aircraft demonstrated that capability Feb. 4, 2005 when they flew a simulated combat mission during their 50th flight at NASA's Dryden Flight Research Center, Edwards Air Force Base, CA.