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GPS-based System May Improve Air Travel

December 12, 2007 at 6:35 PM EDT
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The Federal Aviation Administration has unveiled a new air traffic control system, ADS-B, that incorporates the Global Positioning System to more accurately track airplanes in flight. Tom Bearden examines ADS-B, which the FAA has promised will make air travel safer and easier.

GWEN IFILL: Next, a Science Unit report on a new air traffic control system the government hopes will eventually take some of the hassle out of air travel. NewsHour correspondent Tom Bearden reports.

TOM BEARDEN, NewsHour Correspondent: This is the future of air traffic control. A moving map display tells pilots like Bryce Alber exactly where they are, what other planes are in the vicinity, wherever there are any terrain hazards to avoid, and gives them constantly updated weather information.

How accurate is this?

BRYCE ALBER, Hagland Aviation: Dead on. These things are down to within feet, so they’re very accurate.

New system replaces radar with GPS

TOM BEARDEN: On-board equipment uses GPS, global positioning satellites, to pinpoint the plane's location, somewhat like the familiar navigation devices in cars. Planes then broadcast their position to all other aircraft and also to ground stations that feed computer displays for air traffic controllers.

BRYCE ALBER: It's invaluable for us here. For situational awareness, there's nothing, nothing anywhere else that gives that information it does in one central location.

TOM BEARDEN: The FAA has been testing the technology for the last seven years, paying for it to be installed in approximately 200 aircraft that fly the skies in and around Bethel, Alaska. The technical name is Automatic Dependence Surveillance-Broadcast, or ADS-B.

BRYCE ALBER: All right, folks. Welcome to Bethel. I hope everybody had a good ride there. Please watch your step as you get off and go into the terminal. There is some slippery and icy spots on the ramp.

TOM BEARDEN: Many in aviation industry believe it could help make flying much more efficient and bring relief to tens of thousands of passengers who get stranded by canceled flights every year.

ADS-B will eventually supersede today's ground-based radar technology, which hasn't changed much since the 1940s. Radar is only accurate to within a mile or so of a plane's actual location, so controllers separate them by five miles or more.

Leonard Kirk has been at the forefront of developing the technology.

LEONARD KIRK, University of Alaska, Anchorage: ADS-B allows us to move aircraft closer together safely, because of the greater accuracy and integrity we have with that over radar, so we gain capacity in the airspace. We'll be able to surveil more airspace and provide access to more airports in less-than-ideal weather and so forth.

Alaska makes a good testing ground

TOM BEARDEN: And bad weather is one of the reasons why Alaska is one of the most dangerous places on Earth to fly and why the FAA chose the state to test the new system.

JIM CIEPLAK, Alaska Aviation Safety Foundation: I've used this when you're flying through thunderstorms or, I should say, around thunderstorms.

TOM BEARDEN: Jim Cieplak works for the Alaska Aviation Safety Foundation.

JIM CIEPLAK: During the decade of the 1990s, statistically we had an accident in Alaska every other day.

TOM BEARDEN: And how did that compare with the lower 48?

JIM CIEPLAK: Four to five times greater the fatal accident rate here in Alaska than anywhere else in the U.S.

TOM BEARDEN: Why was that?

JIM CIEPLAK: Multiple reasons. One, it's just the environment here in Alaska, remote areas, weather changes very quickly. You have mountains; you have snowstorms, extreme cold weather. In addition, we have a lack of infrastructure up here, a lack of aviation infrastructure. So radars, communications, weather reporting systems.

TOM BEARDEN: Air travel is just about the only way to get around here much of the year. No roads lead in or out of Bethel, and river traffic comes to a halt in the fall when ice begins to form.

So small aircraft allow Bethel to act as a hub for 52 surrounding Eskimo villages, turning these scattered settlements into a community. Airplanes take people to hospitals and grocery stores, let native Alaskans bring their handmade crafts to market.

Alber took us to a tiny village called Newtok to show us how it all works. It's a typical flight for this part of Alaska, cruising over a seemingly endless, featureless expanse tundra, interlaced with thousands of lakes and ponds.

But the new system makes it easy to navigate. It also receives a continuous stream of weather information that Alber can bring up by punching a few buttons.

BRYCE ALBER: Real quick, I can get the weather in Bethel.

TOM BEARDEN: I gather the weather changes up here pretty quickly.

BRYCE ALBER: It changes real fast, real fast. So if you're out in an area that's down, you want to know where the weather is good. And before if you're down low, we had nothing.

ADS-B promises to reduce crashes

TOM BEARDEN: Perhaps even more valuable is a continuous visual display of potential obstacles. Cieplak showed us how the display can keep pilots out of trouble among the peaks just east of Anchorage.

JIM CIEPLAK: The red terrain is terrain that is at our altitude or above, meaning it's terrain we can hit. As you can see out the window, we do have a lot of mountains off to our right.

TOM BEARDEN: The number-one cause of accidents in Alaska is controlled flight into terrain, aircraft crashing into things the pilot never sees.

JIM CIEPLAK: Now, anticipating where the terrain is, seeing where the other airplanes are relative to you, getting the direct weather uplink data directly to your display all helps pilots make better pilot decisions and, in that case, safer flying all around.

TOM BEARDEN: Back out over the tundra, Alber began his approach to the tiny gravel airstrip at Newtok. His plane was quickly followed by nearly a dozen other flying school buses, bringing children from surrounding settlements to participate in the Native Youth Olympic Games at the Newtok school.

Although most of these students weren't aware of it, the new GPS devices made their trip here much safer.

LEONARD KIRK: We estimated when we started out that we would possibly get a 28 percent reduction in accidents. And we were absolutely amazed and ecstatic, happy, that we got a 47 percent reduction in accidents.

TOM BEARDEN: GPS technology has also helped rescue teams find downed aircraft. John Lane is the support manager at the FAA's Anchorage center.

JOHN LANE, Federal Aviation Administration: We can almost tell the rescue folks exactly where to fly to. And we've had documented cases when that's exactly what's happened. And just within a matter of two hours, we can have somebody on the scene, whereas in the past it may have taken days, if they ever found them at all.

Benefits will be gradual

TOM BEARDEN: The first steps towards installing the system in the lower 48 are now underway. It will take until about 2020 to install the 800 systems believed necessary to cover the whole country, at a cost of about $15 billion. In addition to that, each aircraft will also need to install the GPS devices to take advantage of the new system.

Estimates are it will cost between $200,000 and $400,000 each to equip the 7,600 commercial airliners currently in operation in the U.S., but the FAA argues that ultimately the system will more than pay for itself in cost savings from fewer cancellations and reduced delays.

The owners of small aircraft will have to buy the new equipment, too, if they want to fly into the larger airports. It will cost between $10,000 and $15,000 per plane.

United Parcel Service has been using a version of this technology at its Louisville hub for several years. The company estimates it's been able to fly with a nearly 15 percent greater efficiency, saving almost $1 million in fuel each year.

While many believe this technology will help reduce congestion in the sky, passengers stuck in airports won't see immediate relief from this year's record flight delays.

It's still going to take years to install ADS-B. And while a lot of planes might be flying closer together when it's done, many of them will still be circling the busiest airports waiting for a slot to land, because there aren't enough runways to accommodate the ever-growing number of commercial flights.