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Copyright © 1996 Institute of Electrical and Electronics Engineers.
Portions reprinted, with permission, from IEEE Spectrum, January 1996, The Institute of Electrical and Electronics Engineers, Inc., 345 East 47th St., New York, NY 10017.

IEEE Spectrum

January, 1996


by Dave Dooling, Contributing Editor

Airport '95

Competition among airlines heated up in Europe as carriers took full advantage of the European Union's Third Aviation Package, which extends an airline's license to fly in one European country to every country in the Union. The Union has now exploited the new rules to keep France from restricting non-French airlines from using Orly Airport in Paris.

In the United States the hard-luck Denver International Airport (DIA, its three-letter code) finally opened Feb. 28--16 months late because of problems with a so-called state-of-the-art baggage-handling system that mangled more items than it delivered.

Once the passenger gets to the plane, DIA seems to have justified its planners' hopes. In October, a six-month performance report claimed that DIA was immediately removed from the FAA's list of congested airports and has an acceptance rate of up to 120 aircraft per hour (an average of 1324 per day), 35 percent higher than Stapleton in good weather and 275 percent higher than in bad weather. Its arrival rate was 12 during an October snowstorm that would have closed Stapleton.

DIA also has an impressive suite of 140 FAA facilities in or around the airport to aid pilots. One is a Low Level Wind Shear Alert System, in which 29 wind speed and direction sensor locations report to a central computer linked to a Terminal Doppler Weather Radar system, so as to predict microburst and wind shear activity that might endanger aircraft. Also, an Airport Surveillance Radar lets controllers determine the position of an aircraft with just a single reply from its transponder. Then there are Airport Surface Detection Equipment Radars and an Integrated Communications Switching System, linked by 24 km of six-line optical fiber that transmits color video and data without electromagnetic interference.

Photo of the Traffic Management Advisor, a CTAS tool, being tested at Denver TRACON
[1] Traffic jams in the sky will be greatly reduced with the Center Terminal Radar Control Automation System (CTAS), shown here in testing at Denver International Airport, which will use sophisticated computer graphics to display traffic flow to controllers. Load graphs [top right] predict traffic arrival patterns as moving averages. Timelines [top left] predict arrivals of individual flights. Controllers can then adjust arrival times and thus avoid tie-ups and traffic surges.
Credit: NASA

Denver's suite of pilot-assist tools includes the Center Terminal Radar Control Automation System, or CTAS, being developed for the FAA by NASA's Ames Research Center, Mountain View, California. Senior scientist Heinz Erzberger said that CTAS helps controllers avoid delays when too many planes are lined up in the queue for landing. A traffic management advisor (implemented at Denver and at Dallas/Fort Worth) displays load graphs that show the ebb and flow of traffic from the present moment to an hour in the future, so that controllers can shift aircraft arrivals slightly and prevent traffic jams. Two more components, the descent advisor and the final approach sequencing tool, started testing in late 1995. CTAS will become a vital element in the Free Flight program that in the next century will let pilots fly the most direct and efficient routes to their destinations. Under Free Flight, global positioning systems aboard aircraft will alert aircraft and controllers when another plane enters an alert zone and keep the two from colliding.

Airport and air regulatory authorities felt greater pressure to make the skies and runways safer. The International Air Transport Association (IATA) reported that international airlines earned $1 billion in 1994, the first annual profit since 1989. Even so, the business grew more competitive with the resurgence of cut-rate airlines and discounted rates. The Airports Association Council International, in Geneva, Switzerland, reported that passenger traffic was up 7 percent (to 1.2 billion passengers, according to IATA) and cargo was up 12 percent at 377 leading airports.

At an aviation safety conference, held 12 months ago, participants asked the FAA for broader use of GPS, weather maps transmitted in real time to flight crews, and better anti-collision systems that would include warning radar on airliners, and transponders on smaller aircraft, among other improvements. In an effort to reach for zero accidents, the airlines also agreed to share details of in-flight mechanical and electronics problems with the FAA, provided the information is not used to start legal actions against pilots.

©1996 Institute of Electrical and Electronics Engineers

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