National Airport has been under indictment for years. There has been widespread agreement that it is overcrowded and overused, and now there is an even more widespread perception that its takeoff and landing patterns are dangerous, that its runways are too short for the big jets that use it, that a jet in trouble will end up in the Potomac River. Whatever public confidence existed because of National's safety record has been badly shaken. The verdict is in.

The cause of the Air Florida crash is still unknown, but one conclusion appears inescapable: Whether it was ice, slush, engine failure, or a combination of human error and the elements, the airport was not up to providing the maximum backstop for disaster. The doomed voices of the pilots of Air Florida Flight 90, eerily chatting about the snow and the slush on the ground, have left a chilling record of their perilous takeoff, their inability to even see, and raised major questions about the effectiveness of the de-icing procedures at National. The single jet runway at National, 6,870 feet long, is so short that any pilot would have to think twice before aborting a takeoff on it in icy conditions. While experts point out that under normal conditions a 737 needs only a third of the runway National provided, the accident has neverthless focused attention on the adequacy of the runway for other jets. And it has provided sharp contrast to the three runways at Dulles, the shortest of which is 10,000 feet.

Given all the difficulties of flying in and out of National that the public has become so painfully aware of since the crash, it is something of a miracle that no disasters had occurred since 1949. Traffic at the airport has steadily increased with the growth of carrier size from 6.7 million passengers in 1965 to an estimated 14 million last year, with the PATCO strike. The number of carriers using the airport has nearly doubled to 18 since Congress deregulated airlines in 1978. The facility has changed little.

National's problems are probably more complex than any other airport's in the country. It is subject to jurisdictional pressures from Maryland, D.C. and Virginia, the Federal Aviation Adminstration, which runs it, and Congress. And Congress traditionally has played a pivotal role in maintaining the status quo. It has been loath to cut back on flights in and out of an airport that is 15 minutes from the Hill. National is convenient not only to the members of Congress and their staffs, but to their important constituents--to the mayors and the big businessmen who want to come to Washington for a day to do business with the government. For them, the underused luxury of Dulles doesn't hold a candle to the convenience of National.

Congress, with the exception of oversight hearings last week, has not exactly rushed in to hold more substantive hearings on the Air Florida crash and safety at National Airport. The National Transportation Safety Board report on the causes of the crash will not be out for at least four months. The suspicion here is that the forces of lethargy are gathering and that the safety problems at National highlighted by the crash will remain very much the same. The NTSB does not have the power that Congress has to reduce the flights and therefore reduce the risks of flying out of National, which politically is probably the most obtainable goal. Transportation Secretary Drew Lewis has taken some steps to shift traffic from National to Dulles, but it is going to take an act of Congress--namely, setting its own narrow interests aside in favor of public safety--to meaningfully alter the pressures on National.

Airline safety, airport closing policies, who decides when to fly and when not to fly in bad weather, are fundamentally economic questions that are not unique to National Airport. In Boston, for example, World Airways, a marginal carrier, continued to fly in a snowstorm and its plane ended up in the water. Two other carriers decided not to fly. Airline safety in an economically deregulated system are clearly questions Congress needs to examine, and National Airport--with its proved inability to provide a margin for failure, coupled with its inability to provide instrument landing system approaches from the north--is clearly the place to start. Congress has no business endangering the rest of us, merely for its own convenience.