Weather May Hamper Search for Missing Jetliner

CANBERRA, Australia--Ten planes resumed the hunt in the Indian Ocean for clues to the disappearance of Malaysia Airlines Flight 370 on Monday, including--for the first time--Chinese military aircraft.

Australia's Deputy Prime Minister Warren Truss said two Chinese military Ilyushin IL-76 planes would search an area where a large object was identified by a Chinese satellite Saturday.

"It is a very difficult task. Today we expect the weather to deteriorate. Unfortunately forecasts ahead are not all that good," Mr. Truss said on Monday. "The search area is very large today, around 68,000 square kilometers (26,000 square miles). That's a lot of water to look for a tiny object."

Australian Prime Minister Tony Abbott said on Sunday that authorities have a number of credible leads. They include satellite images of objects in the southern Indian Ocean captured by DigitalGlobe Inc.--a provider of imagery to the Pentagon's geospatial agency--and Chinese images that, at first blush, appeared to be consistent with the earlier satellite photos. The commercial images showed two pieces of debris, the largest of which was around 79 feet (24 meters) long, while Chinese military discovered a large object measuring 72 feet long and 42 feet wide.

"It is still too early to be definite, but obviously we have now had a number of very credible leads and there is increasing hope--no more than hope--that we might be on the road to discovering what happened to this ill-fated aircraft," the Australian prime minister told reporters in some of the most upbeat remarks since his country assumed the lead of the international search almost a week ago.

The chief of Malaysia's civil-aviation authority said Sunday they received new satellite images from French authorities of possible debris roughly 370 miles west of the area where the search is now focused. Mr. Truss said the latest images were outside the zone identified as the most likely area to search for the missing Boeing 777-200 jet--which disappeared carrying 239 people en route from Malaysia to Beijing on March 8.

"Having said that, we've got to check out all the options. We still don't know for certain that the aircraft is even in this area," he said. "We are I guess clutching at whatever little piece of information comes along, to try and find a place where we might be able to try and concentrate the efforts."

One significant discovery by searchers on Saturday was a number of small items, including a wooden pallet surrounded by strapping belts. Australia's maritime authority said wooden pallets were commonly used on commercial aircraft. However, efforts to confirm the initial sighting--made by a civilian plane--were fruitless.

Ocean conditions in the search area are some of the world's roughest, making it a challenge to find floating debris. Sailors have dubbed the area "the roaring 40s"--a stretch around 40 degrees latitude in the southern hemisphere where strong winds can roar like a lion. Ships involved in the search are faced with the problem of looking for debris that may be partly submerged amid continuous rolling waves up to 30 meters (98 feet) high, according to some ocean experts.

Sunday's search found "nothing of note," according to Mr. Truss. Asked whether there was a timeline on when the multinational search could be abandoned, he said the 30-day operating life of the aircraft's black box flight data recorder would be a natural point for reassessment.

"The black box recorder will emit signals for about a month, so that's obviously the first critical point," he said.

Civil and military aircraft from Australia, New Zealand, the U.S., China and Japan are assisting in Monday's search. The broader search operation in the southern Indian Ocean has covered nearly 200,000 square miles (518,000 square kilometers) since it began March 17, nine days after the plane vanished.

Write to Rob Taylor at [e-mail]

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