The U.S. Navy’s Orca drone, also known as the Extra-Large Unmanned Undersea Vehicle (XLUUV), has been in development for years, but will soon be in the hands of sailors as the sea service works to figure out how they will use the capability going forward. The Navy ordered five semi-tractor trailer-sized submersible drones from Boeing Defense in 2019. But like other Navy acquisition programs, the Orca has been hit by cost increases and delivery delays.