(AP) Ÿ Four times this year, the phrase ''NOT UPDATING RADAR AND TIME'' has flashed across radar screens at the FAA's air traffic control center in Chicago. Then, just as suddenly, symbols for hundreds of planes carrying thousands of lives to family, vacations and business have wavered and vanished.
''There's no way to relate to what happens next,'' says Ken Kluge, a controller at the Aurora, Ill., facility. ''It's total chaos. The minute the computer flops, your heart jumps into overdrive.''
Such failures have become common to the nation's frayed air traffic control system. The network has experienced 21 failures since April, caused mostly by computer breakdowns and other equipment malfunctions. The New York center alone has had three failures.
The breakdowns have not resulted in any crashes. But controllers have been forced to rely on backup systems that aren't as sophisticated. And in some cases, they have lost all radio contact with planes in the air.
The immediate problem is aging computers, some of which have 1950s vacuum-tube technology. Maintenance on key computers is delayed for fear of damaging crumbling components for which there are no replacements.
''We're cannibalizing everything we have,'' says Robert Valone, the director of the Federal Aviation Administration's Office of Air Traffic Systems Development. ''The technicians prefer not to touch the equipment for fear something will break.''
But the blame goes deeper. These geriatric computers were to have earned retirement two years ago, replaced with a state-of-the-art system.
Bureaucratic indecision, long procurement delays and the hugely complex software involved forced FAA officials to scrap the original plans in favor of a simpler system that won't be in place until next decade.
The original price tag of $12 billion has tripled to $37 billion, including temporary fixes and the cost of developing the system that was eventually junked. The 10 years estimated to change the system has doubled to 20.
Bob Levin, an assistant director at Congress' General Accounting Office, calls it ''a disaster and a disgrace.''
''The implications are substantial. You're seeing them every time we have an outage that would have been prevented had the system been replaced as scheduled,'' Levin says.
No quick fixes are in sight. Five key control centers will have to nurse old computers another two years.
Until then costly and dangerous failures will plague air travelers as controllers struggle with a system held together by electronic Band-Aids.
''It's like going down the highway knowing your steering wheel could come off at any time,'' says Mark Scholl, a Chicago air traffic controller and local president of the National Air Traffic Controllers Association.
The past four months have been a nightmare of glitches and shutdowns around the nation's system of 350 regional and local traffic control facilities:
˜ South Florida's new radar system fails in thunderstorms. After several incidents, FAA officials cautiously announced they seemed to have fixed the problem by disabling a new piece of software. Three weeks later the radar failed again, blacking out a 400,000-square-mile area for 1 1/2 hours.
˜ Power failures at the Fremont, Calif., center knocked out ground control for Northern California, Nevada and 18 million square miles of the Pacific. Pilots, out of contact with the ground for 15 minutes, were on their own. At least two close calls were reported.
˜ Computer crashes have become a way of life for controllers at centers outside Chicago and New York. Flights are diverted from blacked-out areas and held on the ground for hours.
The Air Transport Association estimates such delays cost the industry $3.5 billion in wasted fuel and under-used aircraft.
''There are contingency plans FAA has to keep the system safe. But there is an enormous cost to us and our customers,'' says Jack Ryan, vice president for air traffic management for the airline trade group.
FAA officials blame much of their troubles on 30-year-old IBM 9020e computers that run displays in Chicago, New York, Dallas-Fort Worth, Washington and Cleveland. The downtime of these computers has more than doubled since 1990.
Controllers rely on these systems to track the identity and position of hundreds of commercial flights traversing hundreds of thousands of miles of airspace. When the primary system fails, backups take over, but often crucial altitude and route information about the blips doesn't reappear on the screen.
Controllers must then scramble to put the information back into the system, using slips of paper with the flight's planned route to identify the blips on the screen.
Other critical features are missing when the backups kick in, including systems that warn controllers when two planes are approaching each other or when they are drifting too low.
''There's a sense of extreme helplessness,'' says Mike Seko, a controller in the Fremont center. ''You know there's a lot of airplanes up there that you feel totally responsible for, but your tools have been taken away.''
The FAA has announced the computers would be replaced Ÿ by 1997. They in turn are to be replaced by a system-wide upgrade scheduled to begin in 1998.
Cost for the 20-month temporary fix: $65 million.
Problems began in 1981, when the FAA embarked on an ambitious program to upgrade the nation's air traffic system. Under the plan, staff members and some 200 facilities would be eliminated by new technology.
But the new system was hideously complicated, requiring 3 million lines of programming. As programmers struggled, bureaucrats tacked on more and more bells and whistles.
Procurement dragged as administrators came and went. The FAA has had five acquisition managers since 1990.
''A variety of factors both managerial and technical went into this debacle,'' says the GAO's Levin. ''It wasn't that people had bad motives; they made bad mistakes.''
The mistakes multiplied. The FAA slowed hiring of technicians and controllers, anticipating a more efficient system. Now, there are fewer technicians to care for the aging machines.
Transportation Secretary Federico Pena has called for 116 new controllers to fill the gap along with more technicians to keep the system running.