Australian authorities heading the southern Indian Ocean search for Malaysia Airlines MH370 reported that the null of the ocean floor this week. The unstated goal is apparently to do a seafloor characterization of the missing Boeing 777-200’s search area.
In a statement, the joint Australian agency coordinating the search efforts said that this decision had been reached over the weekend after a meeting between Malaysian, Australian and Chinese authorities in Perth. There, it was apparently agreed that the Chinese survey ship would, weather permitting, sail for “areas provided by the Australian Transport Safety Board” to begin its mapping operation.
“A bathymetric survey is usually done from the surface, looking at the general topography of the seabed,” said Charitha Pattiaratchi, an oceanographer at the University of Western Australia in Perth. “But from 4500 meters (14,700 ft.) above the seabed, the resolution is pretty poor. So this is unlikely to pick up the airplane debris.”
But because these areas of the southern Indian Ocean have probably been never mapped, Pattiaratchi says that this will offer searchers a “pre-survey” to be able to better prepare the U.S. Navy’s future Bluefin-21 autonomous underwater vehicle MH370 search missions.
Such a bathymetric survey, he says, might also be able to give searchers a better understanding of regions where the Bluefin would be unable to go, simply due to the sheer depth of the ocean.
However, Pattiaratchi notes that because the actual multi-beam bathymetric sonar survey instrument would likely be mounted to the hull of the ship, the Chinese vessel will not be as hamstrung by foul weather as the Bluefin.
“You can cover large areas at pretty high speeds, but it gives you only about a resolution of 100-meters,” said Pattiaratchi.
Meanwhile, after completing its initial sidescan sonar survey some 1500 miles northwest of Perth, the Bluefin arrived at the port of Geraldton, Western Australia on Sunday local time. There it was to receive spare transponder parts for both the submersible itself and transponder equipment onboard the Australian Defence Vessel (ADV) Ocean Shield.
Australian search authorities report that these repairs are “necessary to correct a hardware issue affecting the ability of the transponders to communicate with each other during a dive.”
They note that the problem became apparent during Bluefin-21′s last mission on Tuesday and that once the replacement parts are installed, the Bluefin will be tested in port at Geraldton before proceeding back to the search area.
Although there’s no official word on how long the Chinese seafloor mapping will take, Pattiaratchi says he would expect it to be finished within a matter of days.