Three days after the announcement of what was hailed as the "most promising lead" in the month-long search for missing Malaysia Airlines flight MH370, a US Navy commander indicated that such optimism was temporary.
"As hours pass, our optimism is fading away, ever so slightly," CNN quoted Commander William Marks of the US 7th Fleet as saying.
On Monday, Angus Houston, who heads the Joint Agency Coordination Centre which oversees the massive search operation in Perth, hinted at a possible breakthrough following two instances of pinger signals detected by Australian navy vessel Ocean Shield, one of which lasted two hours 20 minutes.
This followed two earlier detections by Chinese vessel, Haixun 01.
"Clearly this is the most promising lead, and probably in the search so far, it is probably the best information that we have had," Angus had said.
But the signals have since either stopped or could not be detected, prompting fears that the batteries to power the black box's locator beacons could have run out.
The aircraft's black box has a battery life of about 30 days, and it has been 33 days since the disappearance of flight MH370 on March 8, en route to Beijing from Kuala Lumpur.
However, CNN quoted Retired Lt Col Michael Kay of the Australian Air Force as saying that the batteries could operate up to 40 days.
Search is now narrowed to a 29,000-square-mile zone some 1,400 miles northwest of Perth, as compared to the nearly 3 million miles of sea and land search for the plane in the early days.
New Zealand air force personnel Kevin McEvoy told CNN that the main focus of the search now centred around the site where Ocean Shield detected the signals on Saturday.
CNN also reported that air and seaborne traffic was being limited in an attempt by searchers not to roil the waters any further, so that the signals could be detected clearly.
The ever elusive debris of the plane, despite the "promising lead", has led CNN aviation analyst Miles O'Brien to doubt if the signals heard were indeed that of MH370's flight recorders.
"It's either the most extraordinary event, or those pings weren't real," O'Brien said. "It's somewhat befuddling."
Malaysian Insider
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