CAIRO: A French navy vessel using deep-water listening devices has detected signals from one of the black boxes that could explain why the EgyptAir plane crashed into the Mediterranean, investigators said on Wednesday. It is expected to be at least another week before an underwater robot can recover the two flight recorders of the Airbus A320 that went down with 66 people aboard en route from Paris to Cairo on May 19. A digital flight data recorder gathers information about the speed, altitude and direction of the plane, while a cockpit voice recorder keeps track of conversations and other sounds in the pilots’ cabin. The signals were picked up by French survey ship Laplace, which is using acoustic detection systems to listen for the “pings” emitted by the flight recorders, said France’s aviation safety agency BEA. The French navy, in a statement, said the flight recorders still had to be precisely located at a estimated depth of 3,000 meters (10,000 feet).