The search for missing Malaysia Airlines flight MH370 resumed in the Indian Ocean on Monday following a four-month pause.
The GO Phoenix search ship began scanning the ocean bed on Monday morning using a "towfish," a vessel equipped with sonar and video functions that is capable of identifying jet fuel. The search zone is roughly 1,800 kilometers off Western Australia and is estimated to be up to 6.4 kilometers deep, covering an area of 60,000 square kilometers in a path of ocean referred to as the "seventh arc."
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Two additional ships from Dutch contractor Fugro NV, the Fugro Discovery and the Fugro Equator, will join the search this month, Australian Transport Safety Bureau (ATSB) chief Martin Dolan told The Wall Street Journal. Both vessels will be fitted with a towfish.
The search operation for the missing jet was halted for four months as search crews mapped remote parts of the ocean floor. Fugro NV was awarded the contract to conduct the deep-sea search earlier this year and began an underwater survey, called a bathymetric survey, with the help of Chinese ship Zhu Kezhen.
Over 111,000 square kilometers were mapped in the survey, the ATSB said on Friday. Pieces of volcanoes, rugged ridges up to 300 meters high and trenches, some 1,400 meters deep, were discovered on the seabed.
"The recently acquired high-resolution bathymetry (underwater survey) data has revealed many of these seabed features for the first time," the Australian Transport Safety Bureau said in a statement. "It is also revealing finer-scale seabed features that were not visible in the previous low-resolution, satellite-derived bathymetry data."
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The Boeing 777 disappeared from radar on March 8 during a flight from Kuala Lumpur to Beijing with 239 passengers on board. Investigators believe the plane crashed after it ran out of fuel.
"Personally, I'm dubious about the search given that the ocean is so vast, but I do believe that the search has to keep going until they find something, whether it's debris from the plane or any type of object," said Greg Waldron, Asia managing editor at aviation website Flightglobal.
"We need to know what happened, whether it was a technical problem with the airplane or the crew," he added.
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The Australian Transport Safety Bureau previously warned that the entire search process could last for over a year.
Authorities confirmed the new search area in June, located hundreds of kilometers south of the initial suspected crash site, which was based on the acoustic signals believed to have come from the plane's black box. But in May, the Australian government said that "the area [near where pings were detected in April] can now be discounted as the final resting place of MH370."