A new underwater acoustic signal possibly from the crashed Malaysian plane was detected today, raising hopes of an early breakthrough in the arduous hunt for the jet as searchers zeroed in on a smaller area in the Indian Ocean to find its "final resting place".
An Australian naval aircraft picked up an underwater signal in the same area where searchers in ships previously detected sounds consistent with a plane's black box.
The development came on the 33rd day of the search for the Malaysia Airlines Flight MH370 - that vanished mysteriously from radar screens on March 8 with 239 people on board, including five Indians.
While conducting an acoustic search this afternoon, an RAAF AP-3C Orion aircraft detected a possible signal in the vicinity of the Australian Defence Vessel Ocean Shield, said Angus Houston, head of the Perth-based Joint Agency Coordination Centre (JACC) which is leading the search.
"The acoustic data will require further analysis overnight but shows potential of being from a man-made source," he said.
Houston yesterday expressed optimism that search teams will "find the aircraft or what's left of the aircraft in the not too distant future".
"I believe we are searching in the right area but we need to visually identify wreckage before we can confirm with certainty that this is the final resting place of MH370," Houston said.
Finding the black box is crucial to know why the Beijing- bound Boeing 777-200 veered off from its route after taking off from Kuala Lumpur.
The batteries of the black box flight recorders have a life of about 30 days, meaning they either might have been or are on the verge of being drained out.
Stored in a plane's tail, they are designed to begin sending off distinct, high-pitched pings or signals as soon as they come in contact with water.
The Ocean Shield, bearing a special US Navy "towed pinger locator", had picked up two fresh signals on Tuesday that matched a pair of signals detected over the weekend consistent with a plane's black box.
Today, Australian Maritime Safety Authority (AMSA) narrowed down drastically the search area to about 57,923 sq km from yesterday's 75,000 sq km, the smallest yet in the month-long hunt. The centre of the search area lies approximately 2,280 km north west of Perth.
Up to 10 military aircraft, four civil aircraft and 13 ships were assist in today's search for the plane that authorities believe crashed in the Indian Ocean.
The three vessels - the Ocean Shield to the north, and the British HMS Echo and Chinese Haixun 01 to the south -- were focussing underwater.