Drone technology has already moved a step closer to a fully autonomous state in the form of the X-47B, a super-charged UAV developed by the US Navy that can fly itself, and which last week completed the first takeoff from an aircraft carrier. The drone is billed as a non-combat craft, yet its design includes two weapons bays capable of carrying more than 4,000lbs.Britain is developing its own next generation of drone, known as Taranis, that can be sent to tackle targets at long range and can defend itself from enemy aircraft. Like X-47B it has two in-built weapons bays, though is currently unarmed.