The more than 20 countries involved in the search for missing Malaysia Airlines Flight 370 are now pinning their hopes on a 17-foot robotic submarine that can scan and map the depths of the seafloor for possible wreckage. But it's no sure thing the sub will find the plane, which is believed to have crashed more than a month ago in the Indian Ocean.
The U.S. Navy's Bluefin-21 will search about 15 square miles on Monday after being deployed, authorities said, but the search zone continues to include hundreds of miles and shift seemingly by the day. It's estimated it will take the submarine anywhere from six weeks to two months to scan the entire search area. The submarine's dive thousands of feet below the waves comes one week after several acoustic pings believed to be from the plane's electronic "black boxes" were detected. That narrowed the search area to several hundred miles, but no additional pings have been heard, and it is believed the batteries on the black box's transmitters may now be dead.
"I would caution you against raising hopes that the deployment of the autonomous underwater vehicle will result in the detection of the aircraft wreckage -- it may not," said Angus Houston, a retired senior officer with the Australian air force who is overseeing the multinational search. "However, this is the best lead we have and it must be pursued vigorously."
The submarine was scheduled to be deployed from an Australian ship, the ADV Ocean Shield, at about 5 p.m. in Perth, Australia. It is expected the search will test the limits of how deep the submarine can go -- up to 14,700 feet under the ocean, some 100 feet off the Indian Ocean floor. The hunt -- now in its 38th day -- is concentrated about 1,300 miles west of Perth. Flight 370 disappeared March 8 while traveling from Kuala Lumpur to Beijing. It is believed to have diverted southwest toward the open waters of the Indian Ocean for unknown reasons and crashed, killing all on board.
U.S. Navy officials said each mission by the submarine will last about 24 hours. That includes two hours for it to descend, 16 hours of search time, and two hours for it to rise back to the surface. It then takes about four hours for operators to download the information the sub's sensors record.
The deployment of the Bluefin-21 to Australia was reported last month, but Monday marks the first time the submarine will be used. Search officials had sought to narrow the area they are probing further using a black box locator -- formally known in the Navy as the Towed Pinger Locator 25 -- that searches for noises transmitted by the plane's cockpit voice and flight data recorders. The devices emit electronic noises that can be heard from miles away with the right equipment, but have a battery life of about 30 days, and have since fallen silent.
Like the pinger locator, the submarine sent to Perth is operated by Phoenix International Holdings Inc., of Largo, Md., which collaborates with the Navy on many salvage operations. It scans the ocean's floor using a sonar tool known as a multibeam echosounder. It transmits acoustic noises, and produces a high-resolution, three-dimensional map based on how those noises bounce back.
The robot submarine is part of a vast arsenal of unmanned underwater vehicles the Pentagon has at its disposal, but U.S. defense officials have not announced that any additional equipment would be deployed. Adm. Samuel Locklear, the head of U.S. Pacific Command, told Foreign Policy in a March 28 interview that the scope and initial uncertainty about where the plane crashed has complicated search efforts significantly
"I personally had dialogue with both the minister of defense and the chief of defense of Malaysia to make sure we were giving them the right support," Locklear said. "But, this has turned out to be the largest search-and-rescue and search-and-recovery effort probably in the history of mankind. It has been a hard thing, because the circumstances behind it were not clear from the beginning."
The black box locator will be set aside while the Bluefin-21 works, officials said. Aerial searches for debris continue, but may end soon. To date, the U.S. Navy has launched 32 maritime patrol missions in search of plane wreckage, covering 293 hours of flight time and 424,004 square nautical miles, Navy officials said. The service has used both P-3 Orion reconnaissance planes and its new model, the P-8 Poseidon.
U.S. Navy photo