Time Running Out to Find Flight 370 Black Boxes

b_250_0_16777215_00_images_obgrabber_2014-03_fc69fc29a5.jpgJason Reed-Pool/Getty Images (PERTH, Australia) -- On Day 24 in the search for Malaysia Airlines Flight 370, 10 planes and 10 ships will again comb through the southern Indian Ocean for any sign of debris from the jet that was carrying 239 people from Kuala Lumpur to Beijing before it vanished. In spite of all the satellite imagery of large and small objects floating in the water, nothing has been definitively linked to the plane that Malaysian officials say crashed in the ocean under mysterious circumstances.

Monday's operation involves crews from the U.S., Australia, New Zealand, Japan, China, South Korea and Malaysia.

One of vessels, the Royal Australian Navy ship Ocean Shield, is equipped with a black-box detector and an autonomous underwater vehicle.

Finding the black boxes from Flight 370 is critical because they may not be emitting signals for much longer than a week.

Meanwhile, the angry relatives of the airliner's Chinese passengers turned up in Kuala Lumpur on Sunday to demand answers from the Malaysian government. Last week, the prime minister said all had died on the plane but Hishammuddin Hussein, Malaysia's acting transport minister, has since contradicted that announcement, claiming there could be survivors.

The Chinese family members also say they haven't gotten any straight answers from Malaysia Airlines or plane maker Boeing about what might have happened to the aircraft missing since March 8.

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