A bat-winged experimental navy drone executed landings on a U.S. aircraft carrier for the first time Wednesday, marking a major advance in robotic aviation.

A flat gray drone that resembles a giant stingray without a tail, the X-47B glided smoothly onto the flight deck of the USS George H.W. Bush about 130 km off the coast of Virginia. The drone had demonstrated it could take off from a carrier during testing in May, but the landing was considered the most difficult obstacle to surmount given the confined space on the ship and unpredictable conditions at sea.

Navy leaders hailed the event as a milestone in aviation, the culmination of an eight-year, $1.4 billion program to test the feasibility of basing long-range drones on aircraft carriers. "What you saw here is the first of the next generation of naval aircraft and the amazing capabilities it will give us," said U.S. Navy Secretary Ray Mabus, speaking to reporters on the ship.