A United States Navy P-8 Poseidon has been unable to find objects spotted by a Chinese aircraft hunting for clues to the missing Malaysian jet in the Indian Ocean, Australian authorities say.
Australian authorities are leading an international search along a southern arc for Flight MH370, which vanished on March 8 with 239 people on board after taking off for Beijing from Kuala Lumpur.
The New Zealand Orion preparing to take off. Photo: AAP
The objects were spotted by the Chinese aircraft from 33,000 feet, as it was heading back to Perth.
Drift modelling was undertaken on the sighting but the P-8 was unable to relocate the reported objects.
The Chinese Ilyushin IL-76 aircraft spotted two relatively big floating objects and several smaller white ones dispersed over several kilometers.
The official Xinhua news agency carried the report, saying the "white and square" objects were spotted by searchers aboard a Chinese Ilyushin jet. Two floating were "relatively big" and there several smaller white ones dispersed over several kilometres.
The crew reported the co-ordinates as 95.1113 degrees east and 42.5453 south to the Australian command centre as well as Chinese icebreaker Xuelong, which is en route to the area on Monday, AFP reports.
However, Australian authorities later said the US Navy had been unable to find the objects.
The Australian Maritime Safety Authority said its search area also continues to be based on US satellite images of two floating objects taken on 16 March.
Chinese aircraft join search
Chinese aircraft joined nine others from Australia, New Zealand, the United States and Japan on Monday in the search of remote seas 2500km off Western Australia, where it is thought the plane may have crashed.
The search took on a new dimension after the French said on Sunday they had picked up images of possible aircraft debris some 850km north of the present search area.
Two Chinese military aircraft, two Australian P3 Orions and two ultra-long range civilian jets were the first to search the site on Monday. Another ultra-long range jet, a US Navy P8 Poseidon and two Japanese P3 Orions would go later in the day.
Australian Navy tanker HMAS Success is also searching and several Chinese ships are on their way to help find any objects spotted from the air.
Tropical Cyclone Gillian, near Christmas Island, could bring bad weather south, hindering search efforts.
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New theory on malfunction
A new report says military radar shows the plane turned as much as 180 degrees and dived to about 4000 metres - a height at which people can breath without oxygen masks - when it turned from its route to Beijing.
The new detail may support a theory that there was a major malfunction, such as a cockpit fire. Military radar tracking shows that the aircraft changed altitude after making a sharp turn over the South China Sea as it headed toward the Strait of Malacca, a source close to the investigation into the missing flight told CNN.
The plane flew as low as 4000 metres at some point before it disappeared from radar, according to the source. The sharp turn seemed to be intentional, the source told CNN.
The official said the area the plane flew in after the turn was a heavily trafficked air corridor and that flying at the lower height would have kept the jet well out of the way of that traffic.
Origami birds hang with prayers and well-wishes for the missing passengers at a mall in Kuala Lumpur. Photo: AFP
NZ crew remain hopeful
The crew of a New Zealand Air Force Orion remains upbeat, despite another failed attempt to find the airliner. The Orion returned to its base in Western Australia about 4.30am on Monday after its latest search.
RNZAF Squadron Leader Brett MacKenzie was on board that flight and said spotting debris from the air is a difficult task.
"You're travelling in an aircraft that's doing 200 miles per hour. The world is whistling past you and you're looking for an object in amongst the whitecaps. You've got to be concentrating constantly - two, two-and-a-half hours - so a couple of moments of inattention you might miss something that's important."
The search on Sunday was hampered by thick fog and cloud, but acting chief of the Air Force Air Commodore Mike Yardley said the Orion's crew haven't given up hope of finding the airliner. He said searchers have been buoyed by the news radar echoes from a French satellite showing possible debris in the search area have been passed to Australian authorities.
"They think with the weight of evidence they're seeing from the operations staff briefing them that they are in the right area and they're determined to go out there and find something."
Air Commodore Yardley said New Zealand has been asked to provide more staff to analyse data from satellites and search planes. "Weather conditions were not great. We had sea fog right down to the surface of the water in half the area; then 600 foot of cloud in the other half of the area - so not great searching conditions."
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