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Submersible’s First Scan for Jet Wreckage Is Cut Short Submersible’s First Scan for Jet Wreckage Is Cut Short
(about 3 hours later)
KUALA LUMPUR, Malaysia — The search for Malaysia Airlines Flight 370 has moved to the dark depths of the Indian Ocean with the first deployment of an unmanned submersible to scan the seabed for signs of wreckage, officials said Tuesday.KUALA LUMPUR, Malaysia — The search for Malaysia Airlines Flight 370 has moved to the dark depths of the Indian Ocean with the first deployment of an unmanned submersible to scan the seabed for signs of wreckage, officials said Tuesday.
But the inaugural mission of the torpedo-shaped submarine, a Bluefin-21, was cut short because it reached its maximum operating depth of about 2.8 miles, triggering a safety mechanism that forced it back to the surface, the Australian agency coordinating the search said.But the inaugural mission of the torpedo-shaped submarine, a Bluefin-21, was cut short because it reached its maximum operating depth of about 2.8 miles, triggering a safety mechanism that forced it back to the surface, the Australian agency coordinating the search said.
The data the vehicle captured during its abbreviated mission, which occurred late Monday, yielded “no objects of interest,” according to a statement from the United States Navy’s Seventh Fleet, which is overseeing American naval involvement in the search.The data the vehicle captured during its abbreviated mission, which occurred late Monday, yielded “no objects of interest,” according to a statement from the United States Navy’s Seventh Fleet, which is overseeing American naval involvement in the search.
Officials had estimated that the ocean’s depth in that area was about 2.8 miles, possibly deeper, stretching the vehicle’s capabilities. In a news conference on Monday, the lead coordinator, Angus Houston, said that if the challenges were too great for the Bluefin, the authorities would have to bring in another submersible with the ability to dive to greater depths, possibly delaying the search. Officials had estimated that the ocean’s depth in that area was 2.8 miles, possibly deeper, stretching the vehicle’s capabilities. At a news conference on Monday, the lead coordinator, Angus Houston, said that if the challenges were too great for the Bluefin, the authorities would have to bring in another submersible with the ability to dive to greater depths, possibly delaying the search.
Officials said they planned to send the Bluefin back down on Tuesday if weather permitted; the forecast was for scattered showers and isolated thunderstorms with sea swells up to six feet. There was no immediate word, however, on whether the authorities planned to supplement the Bluefin with another submarine.Officials said they planned to send the Bluefin back down on Tuesday if weather permitted; the forecast was for scattered showers and isolated thunderstorms with sea swells up to six feet. There was no immediate word, however, on whether the authorities planned to supplement the Bluefin with another submarine.
The deployment of the Bluefin marked the start of a new phase in the search, shifting the emphasis to the sea bottom.The deployment of the Bluefin marked the start of a new phase in the search, shifting the emphasis to the sea bottom.
The Bluefin, which is equipped with sonar mapping technology, was deployed in the area where four sets of pings were detected during the past two weeks by American technicians working aboard an Australian naval vessel, Ocean Shield.The Bluefin, which is equipped with sonar mapping technology, was deployed in the area where four sets of pings were detected during the past two weeks by American technicians working aboard an Australian naval vessel, Ocean Shield.
The vehicle was expected to spend about 20 hours in the water — two hours to descend to the seabed, 16 hours of exploring and another two hours to ascend. But after six hours, the submersible exceeded its depth limit, officials said.The vehicle was expected to spend about 20 hours in the water — two hours to descend to the seabed, 16 hours of exploring and another two hours to ascend. But after six hours, the submersible exceeded its depth limit, officials said.
In the meantime, planes and vessels continued to scour the ocean surface in hopes of finding debris from the plane. Despite weeks of searching, no debris from the aircraft has been recovered.In the meantime, planes and vessels continued to scour the ocean surface in hopes of finding debris from the plane. Despite weeks of searching, no debris from the aircraft has been recovered.
Up to nine military aircraft, two civil aircraft and 11 ships were scheduled to assist in Tuesday’s search. The aircraft and most of the search vessels were being deployed to areas where debris is likely to have drifted, hundreds of miles from where the underwater pings were detected.Up to nine military aircraft, two civil aircraft and 11 ships were scheduled to assist in Tuesday’s search. The aircraft and most of the search vessels were being deployed to areas where debris is likely to have drifted, hundreds of miles from where the underwater pings were detected.
The decision to deploy the Bluefin, and to shift the focus of the search to the seabed, was announced on Monday.The decision to deploy the Bluefin, and to shift the focus of the search to the seabed, was announced on Monday.
An American team aboard Ocean Shield had been using an underwater listening device, called a towed pinger locator, to trawl for signals from the plane’s flight recorders, commonly known as black boxes.An American team aboard Ocean Shield had been using an underwater listening device, called a towed pinger locator, to trawl for signals from the plane’s flight recorders, commonly known as black boxes.
They detected two sets of signals on April 5 and two more on April 8 in an area about 1,000 miles northwest of Perth, Australia, and hoped to capture more signals to better identify the location of the sources.They detected two sets of signals on April 5 and two more on April 8 in an area about 1,000 miles northwest of Perth, Australia, and hoped to capture more signals to better identify the location of the sources.
But the absence of further pings, together with the belief that the batteries in the black boxes were at the end of their life span, led the authorities to conclude that they were unlikely to detect any further signals and that they needed to change tactics.But the absence of further pings, together with the belief that the batteries in the black boxes were at the end of their life span, led the authorities to conclude that they were unlikely to detect any further signals and that they needed to change tactics.
“It is time to go underwater,” the lead coordinator, Angus Houston, said Monday in Perth. The search authorities believe that the black boxes and the rest of the plane’s wreckage might provide crucial evidence in determining what caused the Boeing 777-200 to veer off its scheduled route from Kuala Lumpur to Beijing on March 8 and vanish with 239 people on board.
But striking a note of caution that has become a motif of his public appearances, Mr. Houston said there was no guarantee that searchers would find the wreck.
“Don’t be overoptimistic,” he said. “Be realistic.”
He added, “It may be very difficult to find something, and you don’t know how good any lead is until you get your eyes on the wreckage.”
The search authorities believe the black boxes and the rest of the plane’s wreckage might provide crucial evidence in determining what caused the Boeing 777-200 to veer off its scheduled route from Kuala Lumpur to Beijing on March 8 and vanish with 239 people on board.
“Despite the lack of further detections, the four signals previously acquired, taken together, constitute the most promising lead we have in the search,” Mr. Houston said Monday. “We need to pursue this lead as far as possible.”
He did not specify the size of the prospective search zone on the seabed, only calling it “a reduced and manageable search area.”
Mr. Houston also said that an oil slick had been detected in the search zone and that samples had been recovered for testing, but that results would not be available for several days. The slick was about three and a half miles from the area where searchers had detected the underwater signals.
Though encouraged by the four signals gathered over the past week and a half, search officials have cautioned that successful identification of the plane could take a long time, with some exploration experts predicting that a search and recovery effort of this sort could take more than a year.
Among the challenges that searchers face in the hunt for Flight 370 is the unfamiliarity of the seabed of the Indian Ocean west of Australia, which has not been fully mapped. Mr. Houston said the seabed was thought to resemble rolling hills but was covered in deep layers of silt, which could impede discovery and recovery of wreckage.
Moreover, the extreme depths in the area will limit the set of exploration tools at the searchers’ disposal.
“I think this is an area that is new to man,” Mr. Houston said Monday, calling the environment “very demanding.”
The Bluefin, made by Bluefin Robotics of Quincy, Mass., and owned by Phoenix International Holdings, a United States Navy contractor in Largo, Md., cruises about 115 feet above the seabed, according to a spokesman for the Seventh Fleet.
Using sonar technology, it will create a high-resolution, three-dimensional map of the bottom that technicians on board the Ocean Shield will evaluate for signs of wreckage. If they see anything in the scans that warrants closer attention, they will outfit the Bluefin with a camera and send it back down to take photos.
Mr. Houston explained that each deployment of the Bluefin was intended to last a minimum of 20 hours and that technicians would take about four hours after each dive to download and analyze the data before launching the submarine on another round trip. The team will have no indication of what the vehicle is seeing until it returns and the data is downloaded.
The Bluefin was expected to cover an area of about 15 square miles during its first trip, officials said. But it was unclear Tuesday how much area it was able to cover during its abbreviated mission.
It could take anywhere from six weeks to two months to scan the entire search area, the United States Navy said in a statement.
The final phase of the investigation would involve the recovery of the black boxes and possibly elements of the wreckage along with corpses to help investigators determine what happened to the plane. The circumstances of its disappearance, currently the focus of a criminal investigation by the Malaysian authorities in collaboration with international investigators, could demand a careful examination of any debris discovered on the seabed.
But officials warned that the search effort was possibly still a long way from that stage.
“I would caution you against raising hopes that the deployment of the autonomous underwater vehicle will result in detection of the aircraft wreckage,” Mr. Houston said. “It may not. However, this is the best lead we have, and it must be pursued vigorously. Again, I emphasize that this will be a slow and painstaking process. We have got to find wreckage visually before we can finally say we have solved this mystery.”
Mr. Houston also clarified that analysts had discounted other underwater signals that a Chinese vessel, Haixun 01, reported hearing on April 4 and 5.
The four sets of transmissions detected by Ocean Shield as well as the oil slick discovered in the same vicinity are “all we have really got,” he said. “We have no visual objects. That is where we are.”