MH370 is not in the Indian Ocean search zone, authorities say

The next stage of the search would be to map the ocean floor near where the plane is thought to have crashed. Photograph: Reuters

The missing Malaysia Airlines plane is not in the #Indian Ocean search zone where acoustic “pings” were detected, the Australian search team announced on Thursday, after a #US navy officer cast doubt on whether the "pings" were from a plane's black box flight recorder.

On a day of dramatic developments in the search for the plane, Australia’s transport safety authority said it had finished searching the area and declared that it “can now be discounted as the final resting place of #MH370”.

An underwater search vehicle, Bluefin-21, has scoured more than 850 square kilometres of the Indian ocean west of Perth since four acoustic signals – thought to be emitted by the missing aircraft’s black box flight recorders – were detected by a towed pinger locator in April.

“The joint agency coordination centre can advise that no signs of aircraft debris have been found by the autonomous underwater vehicle since it joined the search effort,” search authorities said.

“The search in the vicinity of the acoustic detections can now be considered complete and, in its professional judgment, the area can now be discounted as the final resting place of MH370.”

The statement came after claims by a senior US navy officer earlier in the day that the four acoustic signals may have been produced by the search vessel.

“Our best theory at this point is that [the pings were] likely some sound produced by the ship [the Ocean Shield] ... or within the electronics of the towed pinger locator,” the US navy’s deputy director of ocean engineering, Michael Dean, told CNN.

But the US navy said later that Dean’s comments were “speculative and premature”.

The statement by Australian search authorities did not address these new doubts over the origin of the acoustic signals.

Authorities said the next stage of the search would be to map the ocean floor near where the plane is thought to have crashed, a process which a Chinese ship, the Zhu Kezhen, has begun. The mapping is expected to take three months.

A private contractor is expected to begin an exhaustive 12-month search of the mapped area in August.

At the time the signals were picked up, the prime minister, Tony Abbott, said he was “confident that we know the position of the black box flight recorder to within some kilometres”.

The flight, which went missing shortly after leaving Kuala Lumpur on 8 March, has been the subject of an unprecedented multinational search effort. It was destined for Beijing but investigators say it was diverted from the flight path deliberately. -- The Guardian