Just how old is the air traffic control system that keeps our skies safe?
It was the second major failure in 15 months, leading some to say it's about time the country upgraded an air traffic control system that dates back to the 1960s.
"We're using technology that is not nearly as good as what most Americans have in their car," said Geoff Freeman, senior vice president of U.S. Travel Association, which represents airlines, hotels and others in the travel industry.
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The Federal Aviation Administration has a plan to revolutionize air traffic control with a GPS-based system called Next Generation, or NextGen, which has been delayed and isn't expected to be completed until 2025.
Over the last decade, the FAA has scrambled to make incremental improvements to the current ground-based system, but its age is showing.
Freeman called Thursday's problems "another black mark against our national travel system."
"We, as a country, have not put our money where our mouth is and developed a world-class aviation system that we can be proud of," he said. "The delays, the cancelations, the breakdowns in the system are a clear sign that Washington has not taken this problem seriously. Millions of travelers are paying the price for it. Our economy is paying the price for it."
The current air traffic system relies on radar, a series of beacons on the ground and radio communications between pilots and air traffic controllers. Controllers tell pilots over the radio what direction and altitude they should take, guiding them from one ground-based way-point to another.
But the system is not 100 percent accurate. Controllers have a good idea of where a plane is but not a precise location. So, safety buffers are built in.
Jets are usually kept to certain corridors -- or highways -- in the sky. These corridors often do not provide the most direct route, but help prevent jets from colliding. Jets also typically have to keep four to five miles behind other planes. That often leaves planes slowing down or taking routes that are not the most efficient.
The NextGen system would switch from a ground-based system to a satellite-based one similar to the GPS in your car. Using such a system, planes can fly much more precise paths in the sky, learn how close nearby planes are and help planes fly in weather conditions that can slow current air traffic to a frustrating halt.
The new system would also vastly improve the landing process. Currently, planes approach airports in a number of steps; going from 30,000 feet to 20,000 and then cruising, say, 20 miles before descending quickly to 10,000 feet. That pattern is now necessary to keep airplanes separated.
But to stay level at one elevation, the plane's engines must generate thrust. A satellite-guided approach would allow planes to glide into the airports with the engines at idle, conserving fuel and reducing noise.
Most say that today's air traffic system is safe but that safety comes at the cost of speed and efficiency. The hope is that with NextGen, travelers would get both.