The next time you're told your plane won't leave for another 45 minutes, don't blame that controller in the airport tower. ``Don't take it out on him -- if you've got a problem, call us,'' insists Sam Rosenzweig. ``Be assured, it's all well-orchestrated right here.''
``Here'' is the sixth floor of the Federal Aviation Administration headquarters in Washington, D.C. Known as the agency's flow control or air traffic command center, it is a roomful of computers manned around the clock by meteorologists and air traffic controllers from all over the country.
Like conductors of a symphony orchestra, Supervisor Rosenzweig and his colleagues spend their days trying to synchronize the flow of the nation's air traffic and keep it moving in harmony. They routinely watch more than 100,000 landings and takeoffs daily. Their aim is to keep the system from taking in more planes than airport controllers can reasonably handle.
If an airport runway is out for repairs, or bad weather sets in on any region of the country, adjustments are ordered. Traffic headed for that particular airport or region is held back for a time. Usually these planes take the delay on the ground for safety and fuel reasons.
Controllers at the command center, on loan for two years from busy airports around the country, are in effect the nation's air traffic cops.``Airplanes don't move until we tell them to,'' insists John Richardson, one of the architects of the present system. ``Our job is to set up a nice flow.''
They try to predict traffic jams ahead of time and avoid them. Airline flight plans are fed into the FAA's technical computer center in Atlantic City, N.J., and processed into 15-minute traffic predictions for all 240 sectors of airspace controlled by the FAA. Then, if weather or other needs dictate, what the FAA calls a traffic management program goes into effect.
On the day of this reporter's visit, Mr. Rosenzweig explains that the flow control center is doing ``a little Chicago, a little St. Louis, and a little Atlanta.'' Bad weather forced the command center to limit landings at, and takeoffs to, those airports. In Chicago, for instance, a snow shower prompted a flow control program limiting landings to well below the normal rate of 85 to 90 planes an hour. On busier days, Rosenzweig says, there may be as many as 10 programs going around the country, delaying arrival schedules for thousands of aircraft.
This effort to manage air traffic from a national center began with a simple phone on a corner desk here back in 1970. A prime spur: frequent long airborne delays around airports that were wasting costly fuel. More-centralized management of traffic was increasingly seen as a necessity. But Rosenzweig recalls that even then the airlines viewed it as ``big brother'' interference. ``It took a lot of coaxing,'' he says.
The real value of the system was not recognized until a massive firing of controllers following an illegal 1981 strike. Suddenly, the FAA needed to reduce air traffic to a volume that a smaller band of controllers could handle. ``We automatically began to look to flow control to see where the glitches were in the system,'' explains FAA spokesman Dick Stafford.
The command center's selection of a changed number for landings and takeoffs at any airport is negotiable in the early stages and remains its most difficult and controversial job.
``You try to bring as much pressure on the system as it can bear but no more,'' explains Rosenzweig.``You're trying to be fair to both the user and the provider of the service.''
The airline industry often complains that the number is too low. ``The airline folks yell at us if they run delays, and the controllers fuss at us if we get too many planes out there in the system,'' confirms Mr. Richardson, also deputy manager of the command center.
``The FAA has to be very conscious that they don't overload sectors, and we've found that's happened several times,'' says National Transportation Safety Board expert David R. Kelley.
The FAA says delays of 15 minutes or more have been averaging only 1,000 a day and is sharply down from last year. But the ATA says actual delays, by its own computing method, are running longer and occur more frequently than the FAA admits. That dispute is likely to go on for some time to come.
In the meantime, flow control, aimed at minimizing the impact of such delays, is increasingly viewed as a permanent ingredient of air traffic management. The FAA's hope now is to make it much more automated. ``With the demand on the system, especially during peak travel hours, I don't think we'll ever be able to lift [flow control] entirely,'' notes Norbert Owens, FAA deputy associate administrator for air traffic control.