PERTH, Australia – Planes and ships combed the newly targeted area off the west coast of Australia on Saturday for possible debris from the missing Malaysian jetliner, as Australia's prime minister said preparations were progressing on getting a black box locator into the search zone.
Australian officials said that objects spotted floating in the search area need to be recovered and inspected before they can be linked to the plane. The objects, first spotted Friday, include two rectangular items that were blue and gray, and ships on the scene will attempt to recover them, the Australian Maritime Safety Authority said.
"The objects cannot be verified or discounted as being from MH370 until they are relocated and recovered by ships," the authority said in a statement. "It is not known how much flotsam, such as from fishing activities, is ordinarily there. At least one distinctive fishing object has been identified."
Australia's Bureau of Meteorology said a cold front would bring rain, low clouds and reduced visibility over the southern part of the search area, with moderate winds and swells of up to 2 meters (6 feet). Conditions will improve Sunday, although rain, drizzle and low clouds are still likely.
Newly analyzed satellite data shifted the search zone on Friday, raising hopes searchers may be closer to getting physical evidence that Flight 370 crashed in the Indian Ocean on March 8 with 239 people aboard.
That would also help narrow the hunt for the wreckage and the plane's black boxes, which could contain clues to what caused the plane — flying to Beijing from Kuala Lumpur — to be so far off-course.
The U.S. Navy has already sent equipment that can detect pings from the back boxes, and Australian Prime Minister Tony Abbott told reporters in Sydney that the equipment would be put on an Australian naval ship soon.
"It will be taken to the most prospective search area and if there is good reason to deploy it, it will be deployed," he said, without giving a timeframe. Other officials have said it could take days for the ship — the Ocean Shield — to reach the search area.
The newly targeted zone is nearly 1,130 kilometers (700 miles) northeast of sites the searchers have crisscrossed for the past week. The redeployment came after analysts determined that the Boeing 777 may have been traveling faster than earlier estimates and would therefore have run out of fuel sooner, officials said.
Search planes are being sent out from Perth, Australia, in a staggered manner, so at least one plane will be over the area for most of the daylight hours. It is also closer than the previous search area, with a flying time of 2 ½ hours each way, allowing for five hours of search time, according to the Australian Maritime Safety Authority.
The Australian statement said five P-3 Orions — three from Australia and one each from Japan and New Zealand — plus a Japanese coast guard jet, a Chinese Ilyushin IL-76, and one civilian jet acting as a communications relay were taking part in the air search Saturday.
Abbott said the job of locating the debris was still difficult. "We should not underestimate the difficulty of this work — it is an extraordinarily remote location. There are inhospitable seas, it's an inaccessible place, we are trying to find small bits of wreckage in a vast ocean."
The new search area is about 80 percent smaller than the old one, but still spans about 123,000 square miles (319,000 square kilometers), roughly the size of Poland. In most places, depths range from about 6,560 feet (2,000 meters) to 13,120 feet (4,000 meters), although the much deeper Diamantina trench edges the search area.
Flight 370 disappeared March 8 while bound from Kuala Lumpur to Beijing. The hunt focused first on the Gulf of Thailand, along the plane's planned path. But when radar data showed it had veered sharply west, the search moved to the Andaman Sea, off the western coast of Malaysia, before pivoting to the southern Indian Ocean, southwest of Australia.
That change was based on analysis of satellite data. But officials said a reexamination and refinement of that analysis indicated the aircraft was traveling faster than previously estimated, resulting in increased fuel use and reducing the possible distance it could have flown before going down. Just as a car loses gas efficiency when driving at high speeds, a plane will get less out of a tank of fuel when it flies faster.
Martin Dolan, chief commissioner of the Australian Transport Safety Bureau, said a wide range of scenarios went into the calculation.
"We're looking at the data from the so-called pinging of the satellite, the polling of the satellites, and that gives a distance from a satellite to the aircraft to within a reasonable approximation," he said. He said that information was coupled with various projections of aircraft performance and the plane's distance from the satellites at given times.
In Beijing, some relatives of the 153 Chinese passengers on the plane said the shift in the search area added to their confusion and frustration.
"What on earth is the Malaysian government doing?" said Wang Chunjiang, whose brother was a passenger. "Is there anything more that they are hiding from us?"
Investigators continued puzzling over what might have happened aboard the plane. A U.S. official, speaking on condition of anonymity because the official was not authorized to speak amid an ongoing investigation, said the FBI's searches of computer hard drives belonging to pilot and co-pilot, including a flight simulator with deleted files, have yielded "no significant information" about what happened to the plane or what role, if any, the crew might have played in its disappearance.
If investigators can determine the plane went down in the newly targeted zone, recovery of its flight data and cockpit voice recorders could be complicated.
"There are a number of ridges, escarpments and fracture zones that run through this area, so it's a fairly complex area," said Rochelle Wigley, director of the Indian Ocean Mapping Project at the University of New Hampshire. Wigley said determining the ocean floor topography within the search zone depends on its exact coordinates. While investigators appear to be focusing on an area where much of the sea floor is about 6,600 feet (2,000 meters) below the surface, depths may reach a maximum of about 19,700 feet (6,000 meters) at its easternmost edge, she said.
Wong reported from Kuala Lumpur. Associated Press writers Scott McDonald and Eileen Ng in Kuala Lumpur; Kristen Gelineau in Sydney; Rod McGuirk in Canberra, Australia; Nick Perry in Wellington, New Zealand; and Eric Tucker and Matthew Pennington in Washington contributed.