Jon Swaine and Alan Yuhas
theguardian
24 March 2014

Without any confirmed sighting, the mystery of what happened to MH370 is very much unresolved. So what happens next?

The announcement by Malaysian prime minister Najib Razak that MH370 is assumed to have crashed into the southern Indian ocean, with no survivors, had a degree of finality to it. But without any confirmed sighting, let alone recovery of any part of the plane, the mystery of what happened to MH370 is very much unresolved.

What has been found so far?

On Monday, Chinese and Australian search planes spotted several more objects in the sea, about 2,500km (1,550 miles) south-west of Australia, which could be debris from the missing Malaysian jet. An Australian P3 Orion aircraft located two objects: one was described as grey or green and circular; the other orange and rectangular. An Australian navy supply ship, the HMAS Success, could reach the objects within several hours or by Tuesday morning, Malaysia’s defense minister Hishammuddin Hussein said.

A Chinese spotter plane crew, meanwhile, saw two large objects and several smaller ones spread across several square kilometers, state media reported. At least one of the items – a white, square-shaped object – was captured on a camera aboard the plane. A Chinese icebreaker, the Snow Dragon, was headed towards the area and would arrive on Tuesday morning local time.

There have been several earlier potential sightings. On Saturday, images taken on 18 March by a Chinese satellite were released, appearing to show an object measuring 22 metres by 13 metres about 1,550km (960 miles) south-west of Perth. This coincided with an update from the Australian Maritime Safety Authority (Amsa) that a wooden pallet and “strapping belts of different lengths” had been spotted by a civil search plane.

Australian prime minister Tony Abbott first announced on Thursday that a “credible” sighting had been made in the Indian ocean, about 2,500km south-west of Perth, based on satellite imagery of two large objects.

What happens next in the search?

Inmarsat, the British firm handling the electronic “pings” said to have been sent from MH370 for hours after its last contact with the ground, said it had now determined that it must have flown south. While the search had already been focused on the southern of two “corridors” indicated by the plane’s final ping as a potential final location, it had still been officially possible that it could have ended up somewhere to the north.

At the request of the Malaysian government, Australia has been overseeing the search for debris in the southerly search sector, from a military base near Perth. It has deployed four military planes, four civilian jets and two navy vessels. China has dispatched seven ships, including three warships and an ice-breaker, along with two military aircraft. Japan has sent two P3 Orion planes, New Zealand one, and the US is using an elite P8 Poseidon navy aircraft.

The US navy is also moving a black box locator into the region, called a Towed Pinger Locator. In a navy statement, Commander Chris Budde said: “If the wreck site is located, we can hear the black box pinger down to a depth of 20,000ft. Basically, this super-sensitive hydrophone … listens for black box pings.”

The boxes are designed to emit signals for at least 30 days following a crash, in accordance with international law. But depending on the strength of the black box’s battery at the time of a crash, they can continue “pinging” for another 15 days or so beyond that.

Nasa, playing a support role, said it would continue to use satellites and cameras on the International Space Station to search for flotsam. China, Australia and private companies are also continuing to scour satellite data for evidence of the plane.

What are they looking for?

Should investigators identify flotsam belonging to MH370, search planes will guide ships to the area so that they can retrieve debris and begin searching on the ocean floor – which in the south Indian ocean slopes from 2,500 metres deep to about 4,000 metres. If the debris field is found, searchers will try “to backtrack that debris to find the ‘X marks the spot’ where the plane actually hit the water, because that would be the center of the haystack,” David Gallo, a director of the Massachusetts-based Woods Hole Oceanographic Institution, told CNN.

Sonar, special systems and submersibles, including automated underwater vehicles (AUVs) – the deep sea equivalent of drone aircraft – will scan the bottom for wreckage. Though the area still remains too vast for “feasible” undersea search, as France’s Bureau of Investigation and Analysis said in a statement on Monday, investigators will want to find the black box and fuselage. The black box, which comprises both the flight data recorder and cockpit voice recorder, could solve many of the mysteries surrounding MH370, from the plane’s precise course and altitude over time to the status of the autopilot and fuel gauge; the cockpit recorder not only would have recorded the pilots’ voices, but also sounds such as engine disturbances. The condition of the fuselage, meanwhile, could determine whether an explosion took place, and moreover how the plane went down.

Where are they searching?

According to the statement by the Malaysian prime minister, it is now known that the plane’s last known position “was in the middle of the Indian Ocean, west of Perth”. He added: “This is a remote location, far from any possible landing sites.” The prime minister did not elaborate, but his statement suggested that investigators have now narrowed down their search area from the almost three million square miles of sea identified last week as the necessary search zone. However, debris from the plane may since have drifted significantly.

In a statement about the search on Monday, France’s BEA said that while it had been sharing with Malaysian authorities its “experience in the organisation of undersea searches” to find Air France Flight 447, which disappeared in June 2009, the search area remained so vast by the time its officials returned to France that underwater searches were still not possible.

Who will end up writing the final report on what happened?

Amid pressure from the US and China to allow more direct involvement by foreign authorities, Malaysia’s government has so far jealously defended its jurisdiction. Assuming that enough of MH370 is recovered to make an inquiry possible, and the debris is found in international waters, Malaysia is sure to want to oversee any official inquiry and final report into what happened, and why the plane apparently crashed.

The International Civil Aviation Organisation, which is part of the United Nations, has publicly clarified that the state of the airline involved takes the lead in the event of an accident in international waters. As a result, the official report on Air France Flight 447, which crashed into the Atlantic Ocean en route from Rio de Janeiro to Paris, was written by France’s Bureau of Investigation and Analysis.

Investigators have so far been searching an area far beyond Australia’s maritime boundaries, and it seems unlikely that the debris would drift far enough to alter this. If, however, the plane were to be recovered within Australian waters, the responsibility for an inquiry would pass to Abbott’s government. Malaysia would be invited to appoint a representative to the inquiry team.

In any case, those desperate to know precisely what happened may have to wait some time, however. The official report on Flight 447 was not published until July 2012 – more than a year after the flight data recorders were finally recovered.