Missing Malaysia Airlines flight MH370: Black box position narrowed down to 'within some kilometres'
The Australian Prime Minster says teams leading the search for the missing Malaysia Airlines flight MH370 are confident signals being picked up in the southern Indian Ocean are coming from the plane’s black flight recorders.
Tony Abbott told reporters in Shanghai, China, that crews searching for the jetliner have zeroed in on a more targeted area for the source of the pings, first heard on Saturday and then again on Tuesday.
"We are confident that we know the position of the black box flight recorder to within some kilometres," Mr Abbott said during his official visit on Friday. "But confidence in the approximate position of the black box is not the same as recovering wreckage from almost four km beneath the sea or finally determining all that happened on that flight."
The Australian navy vessel Ocean Shield has picked up signals consistent with the frequency emitted by flight recorders. A fifth signal picked up on Thursday is unlikely to be linked to MH370, officials now believe.
"Nevertheless, we're getting into the stage where the signal from what we are very confident is the black box is starting to fade," he warned. "We are hoping to get as much information as we can before the signal finally expires."
The batteries powering the devices' black boxes have a 30 day life expectancy, and it has been more than a month since flight MH370 disappeared on 8 March with 239 people on board travelling from Kuala Lumpur to Beijing.
The authorities want to keep narrowing in on a more precise location for the black boxes before they drop a submersible search vessel, which takes six times longer to cover the same area as the pinger locator dragged by Ocean Shield.
Complicating matters, however, is the depth of the seafloor in the search area. The pings are emanating from 4,500 meters below the surface — which is the deepest the Bluefin 21 can dive.
An Australian air force P-3 Orion, which has been dropping sonar buoys into the water near where the Ocean Shield picked up the sounds, detected the fifth possible signal on Thursday, but Angus Houston, the head of the joint agency coordinating the hunt for the Boeing 777, said in a statement that an initial assessment had determined it was not related to an aircraft black box.
The Ocean Shield has been using a US towed pinger locator to try and locate additional signals on Friday, Mr Houston said. Searches using the pinger locater will continue until officials are certain the flight recorder batteries have ran out.
A document released by the Australian government on Thursday said that although batteries were only designed to last for 30 days, it was likely that the acoustic pingers “would continue to transmit at decreasing strength for up to 10 more days”.
The underwater search zone is currently a 1,300-square-kilometer (500-square-mile) patch of the ocean floor, about the size of the city of Los Angeles.
Up to 15 planes and 13 ships were involved in Friday's search.