The X-47B, an unmanned combat vehicle built as a demonstration aircraft for the U.S. Navy, had its inaugural flight at California's Edwards Air Force Base on February 4, 2011.

Drones, such as the U.S. Navy’s formidable stealth drone, the X-47B, have become a prominent part of warfare. However, the craft is no longer used by the U.S. military. Vigorous trials of the X ...