The New York Times

Toward Friendlier Skies

By David Pogue

http://www.nytimes.com/2008/04/10/technology/personaltech/10pogue-email.html?8cir&emc=cira1

Over the weekend, CBS News “Sunday Morning” broadcast my report about the Federal Aviation Administration’s technology for relieving the nightmarish congestion our air-traffic system faces right now. (You can watch it here.)

It’s called A.D.S.-B (it stands for automatic dependent surveillance--broadcast, if that helps anyone), and it’s essentially G.P.S. for airplanes. It’s really, really cool; I got to ride in a couple of planes that have it installed.

Today, air traffic controllers get their plane-location information the same way they have for 50 years: from a ground-based network of 450 radar dishes.

The radar system is very safe at this point. Last year, there were no fatalities in commercial aviation. But it has all kinds of problems. It’s expensive to maintain. The signal varies with distance and weather. You can’t even put radar dishes in the ocean or in mountainous areas like Colorado or Alaska.

And above all, the long-range radar dishes take 12 seconds to rotate, so the air-traffic controllers get an updated plane positions only once every 12 seconds. (Near airports, the updates are every 5 seconds.) As a result, air-traffic controllers have to keep airplanes 3 miles apart near airports, 5 miles over land, and in places like the Gulf of Mexico where there’s no radar, as far apart as 75 miles.

But A.D.S.-B changes all that. You, the pilot, see an icon for your plane in the center of the screen, and the other planes appear around you, with altitude numbers (“-20” means the guy is 2,000 feet below you). You can zoom in and out, call up the weather map, search your aircraft user manuals, and so on.

At the moment, only the controllers--not the pilots--see where all the planes are. (A 747 pilot told me: “I get in my plane, I take off, I put a paper bag over my head. That's how much I know what's going on around me.”)

That’s one reason there’s a lot of wasteful circling around airports: when things get busy, controllers put airplanes “on hold” until they can deal with them. A.D.S.-B would help pilots maintain their own spacing, with less micromanagement from the controllers, thereby landing far more efficiently.

[...]

-- GregorioIvanoff - 11 Apr 2008
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