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Race is on to find jet’s black boxes before time runs out

The crew of one of the Chinese aircraft used in the search for missing Flight 370 worked at Perth International Airport. Australian officials said rough seas halted the search for the jetliner.

The crew of one of the Chinese aircraft used in the search for missing Flight 370 worked at Perth International Airport. Australian officials said rough seas halted the search for the jetliner.

CANBERRA, Australia — Time is running out to find the crucial keys that could solve the mystery of how and why Malaysia Airlines Flight 370 went down.

After the excruciating 17-day wait for confirmation that the Boeing 777 crashed into the southern Indian Ocean, searchers are racing to locate the black boxes before a battery-powered signal they emit fades away.

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By law, the boxes must be able to send those signals, or pings, for at least 30 days after a crash. But experts say they can continue making noise for another 15 days or so beyond that, depending upon the strength of the black box battery at the time of the crash.

Without the black boxes — the common name for the voice and data recorders normally attached to a fuselage — it would be virtually impossible for investigators to definitively say what caused the crash.

The precise location of the plane is still unknown more than two weeks after it crashed, although Malaysian authorities say a British satellite company has pinpointed its last position in the Indian Ocean, where several countries have reported finding floating debris.

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The new findings do nothing to answer why the plane disappeared shortly after takeoff. More specifically, they shed no light on investigators’ doubts about possible mechanical or electrical failure, hijacking, sabotage, terrorism, or issues related to the mental health of the pilots or someone else on board.

Malaysia’s police chief, Inspector General Khalid Abu Bakar, said Monday the pilots and crew of Flight 370 were still being investigated. He would not comment on whether officials had recovered the files that were deleted a month earlier from the home flight simulator of the chief pilot. All the passengers on the flight have been cleared of suspicion, he said.

‘We’ve got to get lucky. It’s a race to get to the area in time to catch the black box pinger while it’s still working.’

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The search for the wreckage and the plane’s recorders could take years because the ocean is up to 23,000 feet deep. It is possible that what is left of the plane may never be found.

Experts in ocean currents and weather patterns are trying to give searchers their best estimate on where the plane went down, which is where the black boxes — they are really red cylinders — are likely to be located.

“We’ve got to get lucky,” said John Goglia, a former member of the US National Transportation Safety Board. “It’s a race to get to the area in time to catch the black box pinger while it’s still working.”

To “catch” the signal, searchers will be putting to use a high-tech listening device on loan from the US Navy. The Towed Pinger Locators is en route to the search area.

It’s a 30-inch-long cylindrical microphone that’s slowly towed underwater in a grid pattern behind a commercial ship. It will pick up any black box ping emitted from, on average, 1 mile away — but could hear a ping from 2 miles away depending on a number of factors, from ocean conditions to topography to if the black boxes are buried or not.

The listening device is attached to about 20,000 feet of cable and is guided through the ocean depths by a yellow, triangular carrier with a shark fin on top. It looks like a stingray and has a wingspan of 3 feet.

The device sends data up that long cable every half-second, where human operators and computers aboard a ship carefully listen for any strong signals and record a ping’s location. The ship keeps towing the device over the grid so that operators can triangulate the strongest pings — and hopefully locate the black boxes.

Aside from the Towed Pinger Locator, an Australian Navy support vessel, the Ocean Shield, is expected to arrive in the search zone within three or four days, officials said. It’s equipped with acoustic detection equipment that will also listen for pings.

The US Navy has also sent an unmanned underwater vehicle to Perth that could be used if debris is located, the Pentagon said. The Bluefin-21, which can operate at a depth of 14,700 feet, has sonar equipment that can be used to take a closer look at objects under water.

If no strong signals are located before the battery on the black boxes fades away, then searchers must move on to using devices called side-scan sonar that creates an X-ray of the ocean floor, allowing experts to look for any abnormalities in the seabed or any shape that wouldn’t normally be associated with the area.

The sonar devices can be towed behind a ship or used with unmanned minisubmarines that can dive to the ocean floor for about 20 hours at a time, scanning the search area, mapping the ocean floor and looking for the wreckage.

This is how searchers found the wreckage of Air France Flight 447, which went down in 2009 in the Atlantic between Brazil’s northeast coast and western Africa. Underwater search vehicles scanned the mountainous sea floor and sent data back up to experts aboard ships that stayed at sea for a month at a time.

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