When fully implemented, NextGen will allow more planes to fly more closely together on more direct routes, reducing delays, carbon emissions, fuel consumption and noise, the FAA promises. Without it, there will be gridlock in the skies, the agency warns. The demand for air travel is growing on a global scale, too. There will be 3.3 billion air travelers by 2014, according to an International Air Transport Association forecast released this week. That's 800 million more than the number of passengers who flew on the world's major airlines in 2009. China will produce most of the new travelers, the association says. CNN