CANBERRA, Australia (AP) — Australia's prime minister said Wednesday that failure to find any clue in the most likely crash site of the missing Malaysia Airlines jet would not spell the end of the search, as officials planned to soon bring in more powerful sonar equipment that can delve deeper beneath the Indian Ocean.
The search coordination center said Wednesday a robotic submarine, the U.S. Navy's Bluefin 21, had so far covered more than 80 percent of the 310-square-kilometer (120-square-mile) seabed search zone off the Australian west coast, creating a three-dimensional sonar map of the ocean floor. Nothing of interest had been found.
The 4.5-kilometer (2.8-mile) deep search area is a circle 20 kilometers (12 miles) wide around an area where sonar equipment picked up a signal on April 8 consistent with a plane's black boxes. But the batteries powering those signals are now dead.
Defense Minister David Johnston said Australia was consulting with Malaysia, China and the United States on the next phase of the search for the plane that went missing March 8, which is likely to be announced next week.
Johnston said more powerful towed side-scan commercial sonar equipment would probably be deployed, similar to the remote-controlled subs that found RMS Titanic 3,800 meters (12,500 feet) under the Atlantic Ocean in 1985 and the Australian WWII wreck HMAS Sydney in the Indian Ocean off the Australian coast, north of the current search area, in 2008.
"The next phase, I think, is that we step up with potentially a more powerful, more capable side-scan sonar to do deeper water," Johnston told The Associated Press.
While the Bluefin had less than one-fifth of the seabed search area to complete, Johnston estimated that task would take another two weeks.
Prime Minister Tony Abbott said the airliner's probable impact zone was a swath of sea floor 700 kilometers (430 miles) long and 80 kilometers (50 miles) wide.
He said a new search strategy would be adopted if nothing was found in the current seabed search zone.