(Reuters) – A U.S. Navy underwater drone sent to search for a missing Malaysian jetliner on the floor of the Indian Ocean could take up to two months to scour a 600 sq km area where the plane is believed to have sunk, U.S. search authorities said on Tuesday. The prediction coincided with the end to the abbreviated first mission by the Bluefin-21 autonomous underwater vehicle six hours into what was meant to be a […]