Boston — A plan by the Federal Aviation Administration to allow more commercial jets to fly the nation's airways has drawn the attention of Congress and renewed criticism from the National Transportation Safety Board (NTSB). ``I think the FAA's track record - and I'm talking about policymakers resisting the temptation to increase traffic at the expense of safety - has not been good,'' said James Burnett, chairman of the NTSB, in a telephone interview last week. ``So, I have to be concerned about this new attempt to increase capacity.''
Mr. Burnett says he is concerned that pressure from airlines and the public to reduce flight delays prompted the FAA move to cancel most ``in-trail'' safety restrictions, which require controllers to place as much as 10, 15, or 20 miles between aircraft on some heavily traveled routes during ``rush periods.'' Critics contend the move will merely shift delays from the ground to airborne holding patterns. The FAA disputes the claim.
The safety board opposes most, but not all, items detailed in a Dec. 7 FAA directive to air traffic managers nationwide. Beginning March 25, the directive provides for automatic cancellation of all in-trail restrictions of 10 miles or more unless specifically justified by senior FAA air traffic managers in Washington.
Controllers say in-trail restrictions have helped them handle heavy, sometimes barely manageable, traffic. During peak hours traffic continues to reach potentially unsafe levels in some areas, air safety experts say.
FAA managers, however, say that only ``unnecessary'' restrictions will be eliminated. Some day-to-day restrictions needed for safety reasons will be retained, they say.
In more immediate situations, the controller may still take whatever action he deems necessary to safety, John Ryan, the FAA's director of air traffic operations. ``If a controller in Chicago Center decides that right now, because he has too many airplanes he wants to restrict the number entering his sector he can always do that,'' Mr. Ryan says. ``Nobody's going to question him about that.''
But air safety advocates on Capitol Hill say they think the directive will pressure traffic managers to cut more in-trail restrictions than is prudent.
``The underlying problem that you won't see in any memo, is that some of the managers take this as a measure of their performance,'' says Rep. Guy Molinari (R) of New York. ``They will have a tendency to push the system beyond its proper limits in an effort to show compliance with a directive that they feel is a mandate.''
Representative Molinari, a member of the House Public Works and Transportation Committee, says congressional action to investigate or limit the FAA directive or to hear expert testimony about its effects, will likely depend on how much concern controllers and pilots express.
While worried by the implications of the FAA directive, Burnett tempered his remarks somewhat. ``Not everything in it is bad,'' he said.
While most of the FAA's plan runs counter to the NTSB's view of how to maintain safety, Burnett says there is at least one part of it that holds potential for safety improvement ``if implemented properly.''
That part would set limits on the number of airplanes that can safely be handled in each of the 652 sectors of airspace across the country. Sectors would be flagged when the number of aircraft reached 90 percent of capacity. Establishing such ``operationally acceptable levels of traffic'' to prevent overloading air traffic controllers is something the safety board has encouraged the FAA to do for years.
Although maximum traffic levels are a good idea, Burnett warned that ``the thing we have to be concerned about is how do they go about establishing that. Do they establish that at a comfortable level - or, is it going to be at that level we think we can get by with if we're lucky?''
An aide says Representative Molinari plans to recommend to Transportation Secretary James Burnley IV that controllers and managers work together on a facility-by-facility basis to assess how many controllers are needed.
``We don't want to wait 14 months for the FAA to assess staffing standards or for a statistical report to come out,'' the aide says. ``We think they can tell how many they really need.''
Other staff aides working on various Capitol Hill oversight subcommittees said they expected the in-trail restriction issue to come up in congressional hearings in February and March.
One aide on a Senate appropriations subcommittee said the FAA will have to answer Congress on the question: What kind of limitations are we going to have to live with until the FAA's advanced [air traffic control] automation comes into place sometime in the mid-1990s? It is a crucial period, he says, because large air traffic increases are expected.
``We will be interested in what FAA is doing to expedite and improve the quality, not only to air traffic controllers, but their other work forces that are critically short - such as the number of safety inspectors and the maintenance technician work force,'' the aide says.
One crucial point that the FAA has not clarified is just how cutting in-trail restrictions will affect airborne holding. It has been the FAA's stated policy to avoid airborne holding and instead hold aircraft on the ground.
The FAA's Mr. Ryan says the aim of the new policy is to eliminate unnecessary restrictions and their accompanying ground delays. But, because airport capacity is fixed and only so many aircraft can land no matter how many are permitted to take off Ryan acknowledges, ``You have to do a little planning which may require some airplanes someplace will have to sit on the ground and take their delay.'' Safety critics are unclear how airborne holding can be avoided.
``I'm not sure exactly how that works if you have aircraft that are now much closer together all headed for the same point,'' Burnett says. ``How, if the acceptance rate at the airport doesn't go up, do you keep from having to put some of them in a holding pattern? There may be an adequate explanation to it, but I confess I don't understand it.''