(Reuters) – An Australian naval vessel carrying an underwater drone involved in the search for Malaysia Airlines Flight MH370 left port on Saturday on its second mission to scan part of the Indian Ocean where the longest sonar “ping” was heard over a month ago. The Ocean Shield is heading to the area where a signal was first located and heard for some two hours on April 5, about 1,600 km (1,000 miles) northwest of Perth to […]