Government announces plane is not in part of Indian Ocean where searchers previously reported 'pings' from black box

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



On a day of dramatic developments, the Australian Transport Safety Buereau (ATSB) 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 have been emitted by the missing aircraft’s black box flight recorders – were detected by a towed pinger locator in April.



But the search has failed to turn up any sign of the plane, which went missing on a flight from Kuala Lumpur to beijing on 8 March with 239 people on board.

“The joint agency co-ordination 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.”



Australia's deputy prime minister, Warren Truss, told parliament in Canberra on Thursday that the search would move into a new phase beginning in August that could take 12 months.

"The pings were the best information available at the time and that is all you can do," he said.

"We are still very confident that the resting place of the aircraft is in the southern [Indian] Ocean and along the seventh ping line," he added, refering to an arc identified by analysis of satellite communications data from UK company Inmarsat. The search area would now be extended to a 60,000sq km zone along the arc. The ocean floor would be mapped to help the search.

The team was "still confident" that the plane would be found and were "determined" to do so, he said.

The statements 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 and wrongly identified as black box signals.



“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.



The US navy said later that Dean’s comments had been “speculative and premature” but the statement by Australian search authorities did not address these new doubts.

The ATSB 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 Australian 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 latest announcement has fuelled the suspicions of friends and relatives who refuse to believe that the flight can simply have disappeared and insist that passengers may still be alive.

“What do I think of this new twist? I think it is consistent with the tangled mass that is this supposed investigation,” Sarah Bajc, whose partner Philip Wood was on MH370, wrote in an email.

“It is a sad commentary on the situation that family members are rejoicing that there is still a chance that our loved ones are being held hostage by hijackers. It is a better option than dead at the bottom of the ocean.”

