Malaysia's acting transport minister, Hishammuddin Hussein, said he had been briefed by retired Australian Air Chief Marshall Angus Houston Houston, who is leading the multinational search, and was "cautiously hopeful that there will be a positive development in the next few days if not hours" at a news conference.
The Malaysia Airlines flight went missing on March 8, en route to Beijing from Malaysia's capital city Kuala Lumpur, carrying 239 passengers and crew. It is believed to have gone down in the Indian Ocean although no debris from the aircraft has yet been found.
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"I can report some very encouraging information which has unfolded over the last 24 hours. The towed pinger locator deployed from the [Australian ship] Ocean Shield has detected signals with those omitted by aircraft black boxes," Houston told a news conference in Perth.
"Two separate signal detections have occurred within the northern part of the defined search area," he added. "Clearly this is the most promising lead in the search so far."
Malaysia Airlines CEO, Ahmad Jauhari Yahya said the incident had "affected the airline" and there was "a lot of work to do".
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Yahya said based on the experiences of other airlines, it will take six months for an airline to recover its reputation in the market after such incidents,but he said the airline plans to take less time.
The U.S. Navy "pinger locator" connected to the Ocean Shield was trawling an area some 300 nautical miles away from separate reports over the weekend by Chinese patrol ship Haixun 01 of a pulse signal with the same frequency of a black box, Reuters reported.
Probably for the next 24 hours, the Ocean Shield will continue its run over the search area, Houston said.
"We need a good position on the ocean floor to be able to prosecute a quick and efficient search," he said, adding that deep waters made the search operation difficult.