Taxi! Taxi!

Visionaries insist we'll soon be hailing small jets and zipping directly to our destinations. Will the plan fly?

Illustration by Mika Grondahl

Illustration by Mika Grondahl

At Embry-Riddle Aeronautical University on Florida's east coast, neat young students wearing aviator sunglasses criss-cross the manicured campus lawn, heading from one class to the next, or on their way to simulator training or the actual flight line. Most of them dream of becoming airline pilots, flying the big iron. In the center of campus sits a life-size stainless-steel sculpture depicting the very event that propelled them toward their chosen careers nearly 100 years ago: the exact moment when Orville Wright, lying on his stomach, lifted off the ground in the first Flyer. His brother Wilbur stands off the airplane's right wing, having just let go.

If the brothers could only see the mess they created.

The U.S. air traffic system has reached critical mass. In 2001, 570 million passengers boarded airliners, and, despite September 11, that number is expected to grow between 3 and 5 percent annually over the next decade. That's considerably more people than the current system can handle. "In airlines, capacity and demand are on the verge of crossing each other," says the FAA's Peter McHugh, who is working on a NASA-led team that is developing a plan to solve the problem.

The solution, McHugh is quick to point out, won't be found in adding more airports and airplanes. That will only exacerbate the congestion, which is already an all-too-easily roused menace. A problem at one major airport-a security breach, say, or stormy weather-backs up air traffic at all the other major airports. As a result, passengers arrive late, some missing their connecting flights. The current "hub-and-spoke" air traffic system is, well, the hub of the system's flaws. As it works now, you fly a packed airliner from one spoke, say, Kansas City, to the hub, a larger airport such as Chicago's O'Hare. Then you board another crowded jet to the second spoke-Indianapolis, for instance-where you arrive between five and 10 hours after you began your journey. The system is cost-effective and thus very popular with airlines: Most passengers and cargo head through 29 hub airports on their way to one of 600 spoke airports. Passengers, though, hate it. The system may help keep their ticket prices low, but fatigue, wasted time, and the bitter irony of traveling aboard a state-of-the-art commercial jet airplane while averaging only 88 miles per hour, door-to-door, is more than many can take. "The average traveler goes 33 percent out of their way," says Embry-Riddle researcher Ken Stackpoole. "That eats up a lot of time."

And that's where SATS comes in. The Small Aircraft Transportation System-currently being developed by NASA, the FAA, Embry-Riddle, and nearly 60 other aviation-related companies, agencies, and universities comprising the Southeast SATSLab Consortium-could, if its proponents prevail, revolutionize the way we travel. By employing a new generation of inexpensive small business jets and an innovative computerized flight control network, air taxi companies would be able to provide direct service from and into any of the more than 5,000 public-use airports that pepper the national landscape but that have been unusable for commercial flights because they lack the staff and equipment necessary to handle heavy traffic, as well as takeoffs and landings in inclement weather.

Stackpoole paints a refreshingly brisk picture: Under the proposed new system, a passenger in Kansas City would simply log onto a taxi service's reservation system, and an airplane and pilot would be waiting at the local airport. The passenger tells the pilot he wants to fly to a distant suburb of Indianapolis, and he's on his way-cruising at 400 miles per hour and improving average door-to-door speed to 200 miles per hour. Such a system, which Stackpoole says would initially cost passengers about the same as a first-class fare, would take significant pressure off the airlines and could triple the capacity of the air traffic system. But most of all, SATS-which would also serve business flyers and private aircraft owners-could make flying an airplane as easy as cruising down the street in an SUV.

In short, SATS would create a virtual interstate highway system in the sky. The small, newly "smart" airports would be unstaffed and would lack the millions of dollars worth of electronics at major airports that permit foul-weather service: control towers, radar installations, and instrument landing systems. Instead they'd be equipped with less expensive but still remarkably sophisticated computer systems that would automatically plan the flight path. These systems would integrate real-time air traffic information, Global Positioning System navigation, collision-avoidance technology, and preprogrammed knowledge of each airport and surrounding terrain to provide pilots with all the information they need to take off and land at unstaffed airports without the aid of air traffic control or advanced instrument landing skills.

In the cockpit, the complex instruments pilots now rely on to keep their planes flying straight and level in nasty weather (altimeter, airspeed indicator, compass, and so on) will become obsolete. Instead, that information will be included graphically on two "synthetic vision screens" that, in addition to providing conventional instrument data, project the world outside in blue-sky perfection-no matter how socked-in the conditions are outside-and outline in yellow boxes the aerial skyway ahead. The pilot merely has to follow the yellow box road. Eventually, flying may not even be that hard. "The ultimate goal is to make it totally automated," says project spokesman Keith Henry of the NASA Langley Research Center in Hampton, Virginia. "Twenty to 25 years from now, you'll say 'Detroit' and the plane will take you there."

But is SATS the new century's equivalent of flying cars and a helicopter in every garage, a pie-in-the-sky vision that will fizzle in the face of inevitable roadblocks and old-school opposition? "A project to make flying easy and simple is just another of a long string of flashy promises," complains aviation industry analyst Richard L. Collins, an author and veteran of nearly 20,000 hours in light airplanes. Questions of safety also leap to mind: Imagine an overcrowded sky and a system that may or may not be prone to error. What happens when inexperienced pilots who have become dependent on the system are faced with an unexpected crisis? And how reliant should we be on entirely automated systems in the first place?

Henry dismisses these concerns as wildly premature. Passenger-carrying robotic aircraft are mere speculation at this point, he says: SATS as currently envisioned will still require well-trained pilots at the controls. Stackpoole concurs, adding that "there's a chance that the SATS airplane will be able to pilot itself, but that's way off, if it ever happens. We're working on near-term technology." SATS, he continues, is simply intended to ease the demands of instrument flying (and, consequently, training for instrument flying), improve a severely overtaxed system, and capitalize on an existing infrastructure of perfectly serviceable airports that these days might see only a few planes a week, if that many.

NASA and other federal agencies are enthused enough about SATS to have allocated up to $69 million over the next four years for SATS research and development, and the alliance with the FAA and various business partners, including aerospace components manufacturer Goodrich, wireless communications company Harris Corp., and Embry-Riddle, has already produced prototype SATS hardware and software.

Most of that now sits in a building at the Daytona Beach campus of Embry-Riddle that I visited recently to test-drive a generic SATS simulator. Mounted on the black wall ahead of the sim is a large screen that presents a pilots's real-world view. Below, on the sparse instrument panel, are two 10-inch-diagonal synthetic vision screens. The screens are driven by a computer called SmartDeck, engineered by Goodrich. The screen on the right shows a moving map, with real-time color representations of the aircraft's flight path, the terrain, and weather conditions. The screen on the left shows the pilot's-eye view under clear-blue-sky conditions. It displays a series of ever-smaller yellow-line boxes with what looks like an insect-a bee-in the center. That's the highway in the sky. Meanwhile, the perimeter of the left screen displays such information as speed, altitude, and compass heading.

Manipulating a control stick mounted far on my left, I follow the bee, which flies through the boxes 12 seconds ahead of the airplane, turning as it turns and descending as it descends. After a while I spot a runway in the distance, and then look up at the larger screen-Reality. And in Reality everything is muddied by clouds. So I look down and concentrate on the bee as it banks and descends. Having taken instrument flying lessons, I know this view is much friendlier than scanning small round instruments. I fly through the clear-blue skies closer to the landing strip, and then onto the runway. Then I look up to the big screen and see the same runway-a little misty perhaps-just as I hit the centerline.

Computers, of course-not my own flying skills-made that touchdown possible. SmartDeck led me to a near-perfect landing with the help of information it received from the Airport Communications Technology Trailer, a ground station consisting of a collection of servers being developed by Harris that will be stored near airport runways. The servers send information to the airplane about weather, traffic (from live FAA radar feeds), and obstacles on the ground, and calculate and communicate flight path changes. The SATS system works entirely without the input of air traffic controllers, unless the aircraft flies near a large hub or spoke airport or in airliner airspace, which is above 18,000 feet. Then the pilots will have to deal with ATC, just as they do now.

The cost per airport to install a ground station will be $500,000, says Harold Bracket, senior engineer at Harris' Government Communications Systems Division. Compare that to the $5 million minimum needed for a single radar installation and $1 million for an instrument landing system, both of which are necessary for commercial air traffic. But universal installation of the SATS system won't be cheap, either. Setting it up at all 5,400 public-use airports will cost a hefty $2.7 billion. SATS proponents hope that local and state governments, supplemented by federal grants, will foot the bill, seeking financial rewards from increased traffic to local airports. But the program's supporters concede this may be unduly optimistic, and that a variety of joint public/private ventures may be necessary for SATS to get off the ground.

The system's designers are also counting on broad acceptance of the SATS concept to help curtail the loss of public-use airports around the country. Sprawling suburbs are eating up an airport every two weeks. At that rate there won't be any small airports by 2025, when the SATS infrastructure is scheduled to be completed, unless businesses and governments support the local strips in hopes of financial payoffs later.

Another key to the success of SATS will be the development of the next generation of small business jets. There are several on the horizon, including one that is being designed specifically with SATS in mind. The six-seat Eclipse 500, whose prototype was unveiled in July, has a pair of Williams International EJ22 jet engines that each weighs only 85 pounds yet produces 770 pounds of thrust. It can land on runways 2,500 feet long or less, and though it will initially come with its own avionics, the jet will be upgradable to the SATS system when it becomes available. The Eclipse is expected to cost less than $1 million (most new business jets start at $6 million). What's more, operating costs for the Eclipse are expected to be around 56 cents per mile, compared with $2 for most other business jets.

Though the Eclipse 500 won't be certified to fly until December 2003, Eclipse Aviation claims it already has orders through the first quarter of 2006-though the company refuses to say exactly how many planes this represents. Besides Eclipse, other small aircraft makers preparing for SATS include Safire, which is developing a new six-seater jet, the S-26, and Cirrus and Lancair, which are introducing new propeller-driven aircraft with synthetic vision screens that could accommodate SATS transmissions.

Until those airplanes start rolling off the production lines, the consortium will have to settle for less sexy test vehicles. Harris' designers are installing Goodrich's SmartDeck in an older twin-engine Cessna 310. The airplane will fly among three Florida airports that have the first ground station test beds: Melbourne, Daytona Beach, and Sebring (stations at Tallahassee, Gainesville, and Tamiami will be operational next year). Engineers at these airports will monitor all activity between the SmartDeck-equipped aircraft and the cluster of computers in the ground station. They'll be paying particular attention to the accuracy of the landings in Florida's erratic weather conditions.

Indeed, safety is at the top of everybody's list of concerns. It's likely that even though SATS is based on an automated traffic control system, flight monitoring by humans may still be needed-for peace of mind, if nothing else. "There's going to be more airplanes in a lower strata of traffic," says Richard Swauger, technology coordinator for the National Association of Air Traffic Controllers. "It's going to create new safety (requirements) you've never had to have before." Some pilots go a step further and say that computerized flying itself is the real peril of SATS. "I can't even get Windows XP to operate properly on my computer," says Joe Castanza, a Lincoln Park, New Jersey, physics professor with about 1,500 hours as a flight instructor. "Sure, it will make flight training easier for students, and sure, it will open up any airport socked in with zero-visibility fog, but what happens when the computer system goes south? I think it would enable pilots to rely more on computers than they do already, and I think that's dangerous."

That probably won't be a problem, responds Embry-Riddle's Stackpoole. In a twin-engine aircraft there's a triple redundancy: two engine alternators and a 30-minute battery backup; in a single-engine machine there's a double redundancy. "As far as the glass cockpit, if one side goes, the other one backs up the one that goes out," Stackpoole explains.

The SATS consortium has more to prove than computer reliability. By 2005, NASA hopes to demonstrate four key SATS capabilities: higher air traffic volumes at unstaffed airports; lower landing minimums (the weather thresholds at which airports can continue to operate) at these airports; an overall improvement in safety and efficiency; and a plan for integrating SATS into the current system.

Despite the obstacles that must be overcome, SATS holds an allure that is decades old. Science fiction writers and future-focused artists have long fantasized about personal aircraft skimming the skies, rapidly moving people from place to place. If nothing else, NASA's new effort is one very large step to the day when it may be as natural to hail a plane as a yellow checker cab.

Phil Scott has been flying since he was 10. He lives in New York City.