Doane said as many as 14 aircraft were crisscrossing

Doane said as many as 14 aircraft were crisscrossing over the search area Thursday scanning the ocean's surface for any sign of debris.
The Australian air force has been dropping sonar buoys to maximize the sound-detectors operating in a search zone that is now the size of the city of Los
Angeles.
Royal Australian Navy Commodore Peter Leavy said each buoy is dangling a hydrophone listening device about 1,000 feet below the surface. Each buoy transmits
its data via radio back to the plane.
The underwater search zone is currently a 500-square-mile patch of the ocean floor, and narrowing the area as much as possible is crucial before an unmanned
submarine can be sent to create a sonar map of a potential debris field on the seabed.
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The Bluefin 21 sub takes six times longer to cover the same area as the pinger locator being towed by the Ocean Shield, and would take six weeks to two
months to canvass the current underwater search zone. That's why the acoustic equipment is still being used to get a more precise location, U.S. Navy Capt.
Mark Matthews said.
The search for floating debris on the ocean surface was narrowed Thursday to its smallest size yet - 22,300 square miles, or about one-quarter the size it
was a few days ago. Fourteen planes and 13 ships were looking for floating debris, about 1,400 miles northwest of Perth.
Crews hunting for debris on the surface have already looked in the area they were crisscrossing on Thursday, but were moving in tighter patterns, now that
the search zone has been narrowed to about a quarter the size it was a few days ago, Houston said.
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