The resumed search for wreckage from Flight MH370 could be hampered by a chain of undersea volcanoes that run directly through the area, an expert warned on Wednesday.
Gale force winds, driving rain and mountainous seas prevented any sorties being flown from Perth in Australia’s west on Tuesday, but 12 aircraft were due to be airborne on Wednesday, with South Korean planes joining the hunt for the first time.
The presence of the underwater volcanoes means the ocean floor is extremely rugged and constantly being reshaped by magma flows.
“It’s very unfortunate if that debris has landed on the active crest area, it will make life more challenging,” Robin Beaman, an underwater geology expert at Queensland’s James Cook University said.
“It’s rugged, it’s covered in faults, fine-scale gullies and ridges, there isn’t a lot of sediment blanketing that part of the world because it’s fresh (in geological terms).”
“Today’s search is split into three areas within the same proximity, covering a cumulative 80,000 square kilometres (30,000 square miles),” said the Australian Maritime Safety Authority which is coordinating the operation.
Four more Chinese ships joined the marine search on Wednesday after a small Chinese naval fleet arrived in the search zone with two helicopters, said Chinese state media.
The fleet, consisting a missile destroyer, a dock landing ship and a large supply vessel, had sailed for five days at top speed after suspending their search in the Gulf of Thailand last week, said Xinhua News Agency.
The Chinese icebreaker Xuelong, or "Snow Dragon", arrived at the same area about the same time and exchanged information with the naval fleet on radio, it said.
The relatively slow polar research vessel spent five days covering 1,300 nautical miles from Perth.
Visibility was good at up to 10 kilometers, but the search for possible debris was complicated by big waves, Xinhua said.
Videographic: The flight path Malaysia Airlines flight MH370 took
Australian naval vessel the HMAS Success, which was forced to leave the storm-tossed region on Tuesday, has returned and will conduct a surface sweep of a zone where two objects were spotted this week.
Australian Prime Minister Tony Abbott said the search - now in a recovery phase - would continue until there was no hope of finding anything.
“It is not absolutely open-ended but it is not something we will lightly abandon,” he said.
Mark Binskin, vice chief of Australia’s Defence Force, has underscored the daunting size of the area under scrutiny by air crews flying exhausting sorties far from Australia’s west coast.
“We’re not trying to find a needle in a haystack, we’re still trying to define where the haystack is,” he said Tuesday as authorities face the task of retrieving sunken or floating debris, as well as the “black box” flight recorder.
Numerous aerial sightings of suspected debris since the weekend had raised hopes that wreckage would be found. But none has yet been retrieved.
The US Navy has sent a specialised device to help find the “black box” flight data recorder and cockpit voice recorder, along with a robotic underwater vehicle that can scan the ocean’s depths.
Malaysia Airlines confirmed to AFP that the battery which powers the plane’s black box will emit a locator signal of 30 days, once activated by contact with water, giving searchers less than two weeks to find a crash site.
Those efforts will be crucial in determining what caused the Boeing 777 to deviate inexplicably off its intended course between Kuala Lumpur and Beijing, and fly thousands of kilometres in the wrong direction.
Malaysia believes the plane was deliberately diverted by someone on board. In the absence of firm evidence, leading scenarios include a hijacking, pilot sabotage or a crisis that incapacitated the crew and left the plane to fly on auto-pilot until it ran out of fuel.
Two thirds of the passengers were Chinese, and relatives there have accused Malaysia of being deceitful and callous in their handling of the tragedy.
Scores of emotional relatives mounted a protest on Malaysia’s embassy in Beijing on Tuesday, scuffling with guards and abusing the ambassador as they demanded to know what happened to their loved ones.
“Return our relatives,” the family members shouted as they massed at the embassy gates. Another slogan went: “The Malaysian government are murderers.”
Malaysia’s ambassador to China Iskandar Sarudin later arrived at the hotel where relatives are staying, to face an angry tirade. Some shouted at him to kneel before them, while others launched a volley of abuse, calling him a “liar” and “rogue”.
Malaysian authorities have defended their decision to release satellite analysis that determined the plane had plunged into the southern seas far off western Australia, possibly running out of fuel.
On Tuesday, they made public more details of the data used to conclude that the plane was lost.
It said the last complete contact between a satellite that was “pinging” signals to the flight came at 8:11 am Malaysian time (0011 GMT), with another “partial” signal eight minutes later.
The findings, by British satellite communications firm Inmarsat, suggest the plane was in touch nearly two hours after its scheduled 6:30 am landing time in Beijing, and right around the time it would have run out of fuel.
The analysis suggested the plane disappeared for good in the middle of the southern Indian Ocean but Malaysian officials said a precise location could not be determined.