After Optimism of More Pings, Reality of Long Jet Search Settles In
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Version 0 of 1. In the excitement of detecting four bursts of signals that might have originated from the flight recorders of Malaysia Airlines Flight 370, missing for more than a month, Australian officials have waxed optimistic. “Hopefully, in a matter of days, we will be able to find something on the bottom that might confirm that this is the last resting place” of the jetliner, Angus Houston, the Australian official coordinating the hunt, told reporters on Wednesday. But in interviews, specialists in ocean exploration and recovery cautioned that a successful identification might take far longer — weeks or months. Even then, some added, the suspicions raised by the jetliner’s disappearance argued for a painstakingly careful investigation of any wreckage discovered on the muddy seabed. “It’s a crime scene,” said David G. Gallo, director of special projects at the Woods Hole Oceanographic Institution in Massachusetts. “They need to do a forensic investigation, to create a virtual map of the site and all the available evidence. That could be a very slow process.” Pinpointing the location of the recorders on the ocean floor requires a suite of sensors and robots working sequentially through miles of water to narrow the search area and pull the electronic device out of a debris field — a job made all the more difficult by the crushing pressures and inky darkness of the deep, not to mention its unfamiliarity. “It has been said that we know more about the surface of the moon than our own seabed,” Commodore Peter Leavy of the Royal Australian Navy, who is helping to lead the hunt for the missing jetliner, told reporters in Perth. “I think that’s probably right.” The seabed of the Indian Ocean west of Australia is considered an oceanographic cipher, and the little available information suggests the bottom is quite rugged. “It’s likely to have crags and gullies and canyons — even landslides — so it’s going to be a very difficult place to pick out bits of an aircraft,” said Dr. Gallo, who mapped the wreckage of the Titanic and led the 2011 expedition that found the broken remnants of Air France Flight 447 on the Atlantic seafloor, two years after it crashed off the coast of Brazil. The current best guess is that Flight 370 lies 2.8 miles down — thousands of feet deeper than the Titanic (2.3 miles) and the Air France plane (2.4 miles). Flight 370 disappeared on March 8 on a flight from Kuala Lumpur, Malaysia, to Beijing with 239 people aboard. Paul H. Nargeolet, a French minisub pilot who has visited the site of the Titanic wreck dozens of times, noted that varying temperatures, salinities and topographies of the deep can wildly distort the pathways of sound signals, making it difficult to zero in on their origin. “The signal is never in a straight line,” he said. “It’s really difficult.” On Wednesday, the Australians reported that the two sets of pings detected on Tuesday were increasingly faint, suggesting that time for this phase of the hunt was running out. Experts agree that if the signals turn out to be authentic, the search for clues will unfold in distinct stages. The first involves the sensor that the Australian ship Ocean Shield is now towing on a long line to listen for flight recorder pings. The three-foot-wide sensor — basically a waterproof microphone with wings — flies along about a mile down. The next phase of the hunt would involve a brightly colored torpedo-like vehicle about 21 inches wide and 17 feet long. Running about 300 or 400 feet above the seabed, it would use a sonar system to create a map of the bottom. On the Ocean Shield, marine experts would scrutinize its readings for signs of wreckage. If anything was found, the vehicle, made by Bluefin Robotics of Quincy, Mass., and owned by Phoenix International Holdings, a Navy contractor in Largo, Md., would be fitted with a camera and pass about 20 feet above the bottom, seeking to photograph any debris field. Experts say the final stages of the hunt would probably involve the deployment of a large tethered robot with bright lights and claws that could pluck up flight recorders and other evidence. Phoenix’s best model, known as Remora 3, weighs 2.2 tons and stands more than seven feet tall. It is unclear whether the authorities have yet called for a big robot. But shipping it halfway around the globe would take yet more time and more costly equipment. Dr. Gallo, of Woods Hole, said that typically the violent crashing of a jetliner at sea rips the heavy flight recorders off their mounts and leaves them “sitting on the floor.” That, he added, was the case with Air France Flight 447, and that eased their recovery. Most jetliners have two recorders, or black boxes, which are usually orange — the flight data recorder and the cockpit voice recorder. Both sit in the rear section, and experts agree that finding them is likely to be a daunting challenge. “This is not something that’s going to be solved any time soon,” said Alfred S. McLaren, a retired Navy submariner. “We’re talking weeks and months — if not well over a year.” |