MH370 searchers have said electronic 'pings' initially thought to have come from missing Malaysian Airlines flight may not have emanated from the plane at all. A senior Australian naval officer said he 'increasingly suspects' some of the signals detected last month didn't come from the jetliner's black-box flight recorders, piling further doubts over the search effort. Australian naval Commander James Lybrand said of four 'pings' picked up by the U.S. Navy's Bluefin-21 autonomous underwater vehicle, two were too weak to have been from a man-made device. Scroll down for video Sonar 'pings': U.S. Navy's Bluefin-21 autonomous underwater vehicle, that picked up the signals last month, is lowered into the Indian Ocean once more
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Searchers now say 2 of 4 'pings' picked up 'too weak' to be man made
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Comes as satellite firm used in search for MH370 offers low-cost tracking system to prevent another flight disappearing
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Service to be offered to all commercial aircraft with Inmarsat satellite link
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That comprises virtually 100 percent of world's long haul commercial fleet
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Malaysia Airlines Flight MH370 has now been missing for two months
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'This offer responsibly, quickly and at little or no cost to the industry, addresses in part the problem brought to light by the recent tragic events around @placeholder.'