Early in February the U.S. Navy took what may well turn out to be a revolutionary step forward in unmanned-aircraft development when the prototype X-47B made its first flight. It is slated to be the first carrier-based unmanned combat aerial vehicle (UCAV). Unlike similar unmanned vehicles currently in service, it is not a low-performance airplane suited only to the benign environment U.S. forces currently enjoy in Afghanistan. Instead, it is an attack bomber whose stealthy design should allow it to survive in the face of the most sophisticated opposing systems. As such, it is likely to be valuable over the full range of scenarios, not only the counterinsurgency ones typified by the war in Afghanistan. On the other hand, because it is unmanned, it can have the sort of endurance that makes UAVs like Reaper so valuable in the current conflict.