On 18 April 2004, an X-45A released an inert 250-pound precision-guided munition in a successful ground-controlled bombing test — an early UCAV weapons-release milestone, but not autonomous. On August 1, 2004, a single ground-based pilot controlled two X-45As simultaneously in flight. Most remarkably, on February 4, 2005, the two aircraft launched into a patrol pattern, autonomously determined which held the optimum position and fuel load to attack a simulated target, and after one struck, the second engaged a previously undetected threat that emerged mid-mission — all without following a predetermined attack path. Though the program was eventually superseded by the Navy's X-47B, the X-45A had proven that the age of the combat robot had arrived.