The search for missing Malaysia Airlines flight MH370 in the southern Indian Ocean has moved closer to Australia with experts halving the target area. Though efforts so far have failed to find signs of the jet, search co-ordinators at the Australian Maritime Safety Authority remain confident. “With a smaller area closer to Perth and more aircraft, I hope we will do better tomorrow, ” the authority’s emergency response chief John Young said yesterday. He said though the search area had been significantly refined, it was still a very big area. Australian, New Zealand and US planes made four sorties yesterday, focusing on the refined 305,000sqkm — an area about one-third bigger than Victoria. The search for the plane with 239 passengers and crew has entered its 13th day and Australia continues to co-ordinate the search in the Indian Ocean. Mr Young said the planes given the job included two RAAF AP-3C Orions, a US Navy P-8 Poseidon and a Royal New Zealand Air Force P-3K Orion. Five merchant ships responded to a broadcast to shipping on Monday night to keep a lookout in the area. Three had traversed the zone with another two going through today but, like the air search, they made no sightings. Search conditions in the area yesterday were moderate. “This area is vast and remote, ” Mr Young said. “It will take several weeks to cover and it is a challenging operation.” The combined search for flight MH370 now involves 7.68 million sqkm, an area slightly bigger than Australia, after Malaysian Prime Minister Najib Razak said on Saturday the plane flew seven hours towards an unknown destination after it vanished off radar. The 26 countries involved are covering a northern corridor over south and central Asia as well as the Australian southern zone deep into the Indian Ocean. Thailand’s military says its radar detected a plane just minutes after the jetliner’s communications stopped. It said it did not share the information with Malaysia earlier because it was not specifically asked for it. The twisting path took a plane to the Strait of Malacca, where Malaysia tracked MH370. A French expert who took part in the search for Air France Flight 447, which crashed in the South Atlantic in 2009, said finding the Malaysian plane would be much tougher. “Here we simply have no idea of the location of the aircraft because there were no ACARS signals, ” Jean-Paul Troadec, a special adviser with France’s civil aviation accident investigation agency, said. Chinese state media reported on Tuesday that China was expanding its search to waters south-east of the Bay of Bengal and west of Indonesia. Xinhua said nine Chinese ships would be involved and would focus on seas near Sumatra in western Indonesia. United Arab Emirates armed forces have joined the search and will cover a zone south over the Indian Ocean to Australia and north over south and central Asia.