A U.K. warship with advanced undersea listening tools reached the area of the Indian Ocean where a Chinese vessel picked up two signals that may be from black boxes of the Malaysian jet that vanished a month ago.
Up to nine military planes, three civil aircraft and 14 ships will assist in today’s search of 234,000 square kilometers, Australia’s Joint Agency Coordination Centre said in an e-mailed statement today. JACC will hold a press conference at noon in Perth, the agency said in a separate e-mail.
The U.K.’s HMS Echo is part of an international fleet trying to find the plane’s cockpit and flight-data recorders to help unravel the mystery that began when contact was lost with Flight 370 on March 8. No trace of the Malaysian Airline System Bhd. jet carrying 239 people has been found.
“They’re in the process of moving some ships around to go over and help the Chinese see if they can relocate that sound,” said David Gallo, director of special projects at the Woods Hole Oceanographic Institution in Massachusetts, who helped search for Air France Flight 447 after its 2009 crash into the Atlantic Ocean. There’s no certainty in the hunt: There was at least one false ping reported during the Air France search, he said.
The ships are racing against time because the black boxes will only continue sending signals for a few more days, based on their typical 30-day battery reserve. It may still take a week to zero in on the devices and recover them, Gallo said. An autonomous vehicle probably would then be used to map the ocean floor and identify the wreckage, before a remote-controlled device is sent to photograph the plane and recover the boxes, he said.
The water is about 4.5 kilometers (2.8 miles) deep in the southern Indian Ocean area where China’s Haixun 01 patrol ship detected two unidentified signals in the past three days, according to the JACC, which is leading the search. A third sound was picked up by another Australian ship, the Ocean Shield, about 300 nautical miles (345 miles) from where the Chinese vessel was operating.
“We are working in a very big ocean and within a very large search area,” retired Air Chief Marshal Angus Houston, head of the JACC, said at a press briefing yesterday in Perth. “We have had very few leads which allow us to narrow the search.”
The challenge is narrowing the search zone to determine where to listen for pings before the black boxes’ batteries expire. Then it would be getting wreckage to the surface from possibly miles below the southern Indian Ocean, and even then answers may remain elusive.
“All this depends on how much data they can get off the black boxes,” said Jacques Astre, chief executive officer of International Aviation Security in New York and a former commercial pilot. “They’re designed to withstand a lot, but there have been cases where they have been damaged.”
The British and Australian ships have listening equipment that may be better able to find the recorders, while the locator the Chinese ship is using is designed for shallower water.
“In a place where the average depth of the sea water is a couple miles easily, it’s hard to understand how they could hear it,” said Gallo. “We’re going to have to wait to see if any of these sounds that have been heard pan out.”
The Royal Australian Navy’s Ocean Shield is en route to where the Haixun 01 heard the two pings about 2 kilometers apart. The ship may be delayed as it investigates the noise it detected, Houston said.
The Ocean Shield is searching the sea with the U.S. Navy’s Towed Pinger Locator, which can find black boxes at a depth of as much as 20,000 feet, or about 6 kilometers. The Echo uses a similar technology, according to the British navy’s website. The British nuclear submarine HMS Tireless has also joined the search.
Flight 370, a Boeing Co. 777-200ER, was deliberately steered off its intended flight path to Beijing from Kuala Lumpur and onto a course that ended in the southern Indian Ocean, Malaysian Prime Minister Najib Razak has said. Investigators have relied on the limited contact between Flight 370 and a satellite to draw up possible paths for the jetliner after it vanished from civilian radar.
Air France 447
The pulses detected by the Chinese ship were at a frequency of 37.5 kilohertz, China’s official Xinhua News Agency said. While black-box locator beacons transmit at that frequency, there’s been no indication the signal is related to the jet.
Black boxes use that frequency so it can’t be confused with background noises, such as whales or seismic events, according to Astre. Hearing the transmitters, or pingers, can be difficult if they are blocked by undersea mountains. Layers of water with different temperatures can also muffle sounds.
While the boxes are designed to operate at depths of more than 6 kilometers, the range of the beacons’ pings is 1.6 kilometers, according to manuals from Honeywell International Inc., maker of the equipment. That may make the signals hard to detect even if an underwater microphone is over the correct location.
In the search for the wreckage of Air France Flight 447, authorities were able to focus on a 17,353-square-kilometer area after finding objects adrift five days following the crash.
Even with those clues, the pings from Flight 447’s recorders weren’t picked up. It was almost two years before the main wreckage of the plane was found, at a depth of 3.9 kilometers, and its black boxes were retrieved.
“At this point, where there’s almost no clues, everything has to be checked out,” Gallo said. “Otherwise, that haystack is huge.”