Easing airline delay is just one of many suggested safety reforms

The call by the Federal Aviation Administration (FAA) for the nation's airlines to stop bunching flights during peak hours at the busiest airports - under threat of government action - has been widely applauded as the way to end delays for thousands of passengers.

But veteran aviation-watchers warn that it is only a short-term, temporary answer to the growing problem of airport congestion. And they are concerned that such a one-dimensional solution could divert public attention from the need to speed up action on other important fronts.

These, they say, include ensuring that there are enough air-traffic controllers (the system is still recovering from the firing of 11,400 three years ago). Also important are computerization of the largely manual traffic-control system and expansion of airport capacity. Chicago, for instance, has a $1.5 billion expansion program under way at O'Hare Airport that is expected to increase gate space 50 percent by the end of the decade.

Airplane traffic around the country is now 8 to 9 percent above prestrike levels. And passenger delays during the first six months of this year were up 73 percent. There has also been a sharp increase this year in the number of incidents in which planes pass closer than permitted.

''We've seen a number of indicators over the last six months that the system is in serious trouble,'' says Mike Hancock, executive director of Ralph Nader's Aviation Consumer Action Project (ACAP). ''There had to be some relief, and this is probably a good short-term arrangement. But our preference is not to cut down on the number of flights.''

The airlines are halfway down the road to deregulation - the lifting of Washington's controls over rates and routes - which Congress mapped out for them five years ago. While some of airlines initially balked at the plan, most now publicly insist they prefer free-market competition to Civil Aeronautics Board (CAB) controls.

Yet in many ways the current traffic crunch at busier US airports is the direct result of deregulation. The number of airlines competing for business has nearly quadrupled since 1978. Many commuter flights now use smaller planes than before and require more airspace separation from larger aircraft on takeoff and landing, says FAA spokesman John Leyden.

Also, the airline industry's move to a more efficient system of flying to central ''hubs'' and transfering passengers to flights to their specific ''spoke'' destinations gives the traveler more choice but increases the burden on controllers. ''It's the hubbing that's caused the air-traffic problems. ... They're all coming in at the same time,'' notes Ms. McConnell.

The airlines lay blame for the current scheduling snafu largely on the FAA's failure as yet to rebuild the air-traffic-control system. And they are concerned that the agency's insistence on rescheduling marks a retreat to reregulation. ''We're much too far down the road to ever go back,'' says American Airlines spokesman Al Becker.

The FAA wants the airlines to do the job themselves if the CAB will grant them antitrust immunity, as Eastern Airlines has requested. CAB spokesman Alan Pollock says the agency is likely to grant the request and send an agency observer to the talks.

But it is far from clear that the airlines could agree among themselves on who should give up which departure times. ''We're willing to sit down and talk, but we don't see much point if all carriers aren't represented and participating ,'' says American Airlines' Mr. Becker. And United Airlines, the nation's No. 1 carrier in domestic flights, is noncommittal even on the idea of a meeting. ''We're still in the process of evaluating what's being proposed - historically we've been opposed to something like this, because it flies in the face of competition,'' says United spokesman Joe Hopkins.

Therefore the FAA, set up primarily as a safety watchdog, may well have to move into the economically delicate business of setting schedules itself.

Spokesman Leyden says the FAA is also considering changes in its own flight rules, such as shortening vertical separation limits above certain altitudes, to speed up the flow of traffic. And he says the agency continues to reassess its manpower and technology needs. New computer software is being sent out to traffic-control centers that can more accurately predict worker overloads in various sectors, for instance. And earlier this month, FAA Administrator Donald Engen said he hoped to have 14,400 controllers (1,100 more than the present force) aboard by the end of the year and that he would consider hiring more.

Some 2,300 experienced controllers are eligible to retire this year, and a bill by Rep. Elliott H. Levitas (D) of Georgia would sweeten financial incentives for them to stay aboard longer. In the meantime, pressure to rehire at least some of the fired controllers has been building.