It 's another small sliver of information in the expanse of mystery surrounding Malaysia Airlines Flight 370 . A failed satellite phone call suggests the missing passenger jet may have turned south slightly earlier than previously thought during its enigmatic journey , Australian authorities said Thursday . After Flight 370 dropped off radar on March 8 , Malaysia Airlines ground staff tried to make contact with the plane using a satellite phone , Australian Deputy Prime Minister Warren Truss said at a news conference in the Australian capital , Canberra . The attempt was unsuccessful , he said , but subsequent analysis of the failed call has given experts a better idea of the aircraft 's position and where it was traveling . The latest analysis of the available data has put a focus on southern parts of the search area in the Indian Ocean , Truss told reporters . MH370 vanished with 239 people on board during a flight that was meant to go from Kuala Lumpur , Malaysia , to Beijing . The search operation , described by Australian officials as the largest in history , has so far turned up no debris from the plane . International aviation experts have relied on information from radar and satellites to try to plot the Boeing 777 's course , concluding that it went down in a remote part of the southern Indian Ocean , far off Australia 's west coast . The experts are sticking to the same vast search zone announced in June , Truss said at the news conference Thursday . But some of the information that the analysts now have suggests that areas of the zone farther to the south may be of `` particular interest , '' he said , noting that the focus of the search continues to be refined as experts keep reviewing the available data . Uncertainty over location of turn . Flight 370 was last detected by radar flying northwest over the sea between Peninsular Malaysia and the Indonesian island of Sumatra . A series of subsequent communications between satellite systems and the errant plane -- known as `` handshakes '' -- determined that at some point , MH370 turned south toward the southern Indian Ocean . It was initially assumed that the southern turn took place at the northwestern tip of Sumatra . But the team of experts has since said there 's no conclusive evidence about where the turn to the south took place . To calculate the current search area , they said they took two approaches to the uncertainty surrounding the turn . They analyzed the satellite data using a range of assumed locations for the turn , and also without any assumption of where the turn took place . The final radar detection of MH370 , by the Malaysian military , occurred nearly an hour after the plane had veered off its planned course . Three minutes later , a satellite handshake indicated that the plane was still traveling northwest . The unanswered phone call took place 14 minutes after the handshake , according to information previously released by Australian authorities . Just over an hour later , a second handshake suggested that the plane had turned and was heading south or southeast . It 's unclear from Truss ' comments Thursday how much more clarity the analysts now have on the timing and location of the turn . The crucial question of why the aircraft flew wildly off course also remains unanswered . Without the aircraft 's wreckage and flight recorders , investigators are struggling to piece together what happened . How flight attendants keep flying after air disasters . Undersea volcanoes . The search for the remains of the plane and the people on board remains primarily focused on a 60,000-square-kilometer area , roughly the size of West Virginia , in the southern Indian Ocean . An underwater search that will involve three ships is expected to start in the area next month , using a range of sophisticated sonar equipment . The process is expected to take about 12 months , Truss said . Officials hope as much searching as possible can be done in the next few months before weather conditions are likely to deteriorate , he said . Ships have already been mapping the undersea terrain in the isolated swath of ocean to help the searchers . Much of the geography of the area was previously unknown before MH370 's disappearance drew attention there . The mapping process has revealed dramatic new challenges for the search teams . The `` remarkable geographic features '' discovered by the surveying include at least two volcanoes and an area where the seafloor drops away from a depth of 600 meters ( 1,970 feet ) to 6,600 meters ( 21,650 feet ) over a short distance , Truss said . `` It would not be safe to put the towed sonar equipment into the water if we did n't have this kind of information about the seabed , '' he said . How long will the search continue ? Cost of search to be shared . Truss spoke after meeting with Malaysian Transport Minister Liow Tiong Lai and Chinese Vice Transport Minister He Jianzhong . Liow said at the news conference that Malaysia 's financial contributions to the search will match Australia 's commitment . Australia has estimated a yearlong underwater search will cost $ 48 million . The Australian Transport Safety Bureau is overseeing the underwater search at Malaysia 's request . The majority of the people on board MH370 were Chinese . All countries involved remain `` cautiously optimistic '' that the wreckage of the missing plane will be found , Truss said . Malaysian couple charged with alleged theft from MH370 passengers .
Official : Airline staff tried to reach the plane by satellite phone after it dropped off radar . The call failed , but later analysis has given experts a better idea of MH370 's position . The Indian Ocean search zone for the missing aircraft remains the same . Some areas a little to the south may be of `` particular interest , '' Australian deputy PM says .