Military officer Duong Van Lanh works within a Vietnamese airforce AN-26 during a mission to search the missing Malaysia Airlines flight MH370 off Tho Chu islands March 11, 2014. The so-far fruitless search for a missing Malaysian airliner entered its fourth day on Tuesday. The massive search has drawn in navies, military aircraft, coastguard and civilian vessels from 10 nations, but failed to turn up any trace of the Boeing 777-200ER that vanished about an hour into a flight from Kuala Lumpur to Beijing early on Saturday. [Photo/Agencies]