The search for the missing Malaysia Airline plane has failed to find any debris in the Indian Ocean despite the hunt being stepped up.
Nine aircraft and eight ships from half a dozen countries scoured the area on the busiest day for the search since Australia began co-ordinating the operation almost two weeks ago.
More than 250,000 sq km of ocean was searched on Sunday as the operation was intensified.
But although more debris was spotted from the air the only items retrieved from the water so far were not believed to be from flight MH370.
One of the vessels being sent to the area where investigators believe flight MH370 is most likely to have crashed has been fitted with a black box detector.
The equipment, known as a hydrophone, will be towed behind the ship to listen for acoustic signals from the Boeing 777's data recorders.
The equipment may hold vital clues about what happened to the plane, although time is running out to find it as its batteries could die in little more than a week.
As well as the black box detector, which can trace pings emitted from depths of up to 6,000 metres, an autonomous underwater vehicle will be used to search for any debris hidden from view beneath the surface.
On Saturday, a Chinese aircraft saw three items - two of which were red and white, the same colours that feature on the outside of the plane - and a Royal Australian Air Force plane spotted multiple objects in the search area, about 1,100 miles off Australia's western coast.
However, the Australian Maritime Safety Authority said most of what had been recovered was "fishing equipment and other flotsam".
"My understanding from this morning is that there has been no discrete debris associated with the flight," Australian Navy Commodore Peter Leavy told reporters.
He said the search in the new zone was complicated as it was in a shipping lane where there was a considerable amount of rubbish floating.
The US Navy officer in charge of the Towed Pinger Locator (TPL) told journalists in Perth that the lack of information about where the plane went down has seriously hampered the search.
"Right now the search area is basically the size of the Indian Ocean, which would take an untenable amount of time to search," he said.
"If you compare this to Air France flight 447, we had much better positional information of where that aircraft went into the water."
Australian Prime Minister Tony Abbott has announced a new co-ordination centre to lead the search for flight MH370 and provide a single point of contact for distraught families.
Based in Perth, the centre will be led by the country's former chief of the defence.
It will co-ordinate the contacts between nations taking part in the search and ensure families get all the information and help they need.
Mr Abbott said the Australian government "won't rest until we've done everything we reasonably can to get those families and to get the wider community of the world a little more peace and a little more insight into exactly what happened".
So far, even though more ships are scouring the area off western Australia, none of the recovered items has been connected to the flight.
Chinese relatives of passengers on board flight MH370 have flown from Beijing to Kuala Lumpur to meet top officials in the investigation.
They have accused authorities in Malaysia of "delays and deception" and demanded they be told the "truth" about what happened.
Also in the Malaysian capital, teams and spectators at the F1 Grand Prix observed a minute's silence for the victims and drivers wore helmets reading "Pray for MH370".