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How Can Air Traffic Controllers Lose a Plane?By VOA14 March, 2014From VOA Learning English, this is In the News.The search for a Malaysia Airlines passenger jet expanded this week. The airplane, a Boeing 777, disappeared last Saturday on a flight from Kuala Lumpur to Beijing. It was carrying 239 people. At first, the search was along its expected flight path. But by week's end, crews had expanded the search across parts of southern Asia for any evidence of Malaysian Airlines Flight 370.With satellites and other technology available, how can a plane as large as the "Triple-7" just disappear? Air safety expert John McGraw says it is easier than you may think.Search area for flight MH370"People are under the impression that every airplane, even when it's flying across the ocean, is observed on some kind of radar scope, with a human being looking at that scope. And it's just not the case. Radars don't reach that far."But John McGraw says there are also a lot of devices inside the Triple-7 that can help searchers follow its movement. Systems in the aircraft send altitude, weather conditions, position and speed to air traffic controllers. There are also at least three ways the pilots can communicate with controllers. Another tool is the flight data recorder or "black box." If the plane is downed in the ocean, the black box sends out a signal that can travel up to three kilometers away.Many people remember when a French passenger jet disappeared five years ago. Air France Flight 447 went missing as it flew from Brazil to Paris. Its wreckage was eventually found in the Atlantic Ocean.Air safety expert John McGraw remembers the National Transportation Safety Board taking action after the Frenc...