Jet search area is too deep for submarine

Phoenix International’s Chris Minor, left, and Curt Newport inspect an autonomous underwater vehicle before it is deployed from ADV Ocean Shield in the search of the missing Malaysia Airlines Flight 370 in the southern Indian Ocean. The search area for the missing Malaysian jet has proved too deep for the robotic submarine which was hauled back to the surface of the Indian Ocean less than half way through its first seabed hunt for wreckage and the all-important black boxes, authorities said on Tuesday.

Lt. Kelli Lunt/ Australian Defense Force

×

Phoenix International’s Chris Minor, left, and Curt Newport inspect an autonomous underwater vehicle before it is deployed from ADV Ocean Shield in the search of the missing Malaysia Airlines Flight 370 in the southern Indian Ocean. The search area for the missing Malaysian jet has proved too deep for the robotic submarine which was hauled back to the surface of the Indian Ocean less than half way through its first seabed hunt for wreckage and the all-important black boxes, authorities said on Tuesday.

Lt. Kelli Lunt/ Australian Defense Force

PERTH, Australia – The search area for the missing Malaysian jet has proved too deep for a robotic submarine, which was hauled back to the surface of the Indian Ocean less than hallway through its first seabed hunt for wreckage and the all-important black boxes, authorities said on Tuesday.

But after only six hours of its planned 16-hour mission on the sea bed, Bluefin 21 – the autonomous underwater vehicle – exceeded its maximum depth limit of 15,000 feet and its built-in safety feature returned it to the surface, the search coordination center said in a statement on Tuesday.

What if anything it might have discovered during the six-hour search was still being analyzed, it added.

The Bluefin 21 will resume the search Tuesday when weather conditions permit, it said.

Search authorities knew the primary wreckage from Flight MH370 was likely lying at the limit of the Bluefin’s dive capabilities. Deeper diving submersibles have been evaluated, but none is yet available in the search area.

The sub would have been programed to return to the surface once it exceeded the 15,000-foot limit, but a safety margin would also have been included to protect the device from damage if it went a bit deeper, said Stefan Williams, a professor of marine robotics at the University of Sydney.

“Maybe some areas where they are doing the survey are a little bit deeper than they are expecting,” he said. “They may not have very reliable prior data for the area, so they have a general idea. But there may be some variability on the sea floor that they also can’t see from the surface.”

Meanwhile, officials were investigating an oil slick about 3.4 miles from the area where the last underwater sounds were detected, said Angus Houston, the head of a joint agency coordinating the search off Australia’s west coast.

Crews have collected an oil sample and are sending it back to Australia for analysis, a process that will take several days. Houston said it does not appear to be from any of the ships in the area but cautioned against jumping to conclusions about its source.