The federal government has decided to install at Baltimore-Washington International Airport a new kind of radar that should make it possible to build a second long runway to accommodate growth and attract new airline service.
"This is excellent news for the airport's future," Nicholas J. Schaus, the Maryland Aviation Administration's deputy administrator, said yesterday.
The Federal Aviation Administration has awarded a $33.7 million contract for the new radar to Allied-Signal Inc.'s Bendix Communications Division in Towson. Bendix designed the system and will manufacture it in Towson, where it has about 1,200 employees.
In addition to BWI, the new radar will be installed at airports in Atlanta, Minneapolis, Memphis and Raleigh, N.C.
By providing a nearly constant fix on the planes as they approach for landing, the new radar will permit parallel runways to remain operating during unfavorable weather. For safety reasons, airports can operate only one of two parallel runways when planes are making instrument landings using current technology.
In addition to increasing airport capacity, the new radar will have another important effect: It will allow parallel runways to be built much closer together. Under current FAA rules, parallel runways must be four-fifths of a mile apart. Because the new radar is more effective in tracking planes, airports would be able to operate runways less than a half-mile apart.
BWI's plan calls for the construction of a new east-west runway in the second half of this decade.
Under the current rules, there is room enough to build only an 8,000-foot runway. With the new radar, the runway could be built closer to the existing one, moving it to the widest portion of the airport and extending the possible length to 10,000 feet or 11,000 feet, Mr. Schaus said.
The existing east-west runway is 9,500 feet long, not long enough to handle jets of some of the long-range international carriers that the airport hopes to attract. Plans call for that runway to be extended to 10,500 feet, with construction beginning as early as next spring.
The distinctive feature of the new radar, which is paid for by the federal government and not the state of Maryland, is its speed.
Conventional radars update the position of airplanes as they rotate once every five seconds. The new radar would provide a fix 10 times more frequently, allowing controllers to see quickly whether a plane was straying toward the "no-transgression zone" that separates the two runways.
The radar also will have color monitors that will alert controllers of problems as they develop. Planes that are heading toward the prohibited zone will appear as yellow on the screen. If a plane actually enters the zone, it will appear as red and an alarm will sound.
Even though many airports nationwide are operating near their capacity, "we're not going to build new airports," said William C. Reed, a marketing official for Bendix.
The new radar will help airports accommodate growth by permitting them to handle more traffic safely, he said.