Just a year ago, the world was riveted to television, monitoring the 17-day hijacking of TWA Flight 847 to Beirut. This summer, the fears raised by that event and by other acts of terrorism that followed are taking a toll on international air travel. But while airlines are trying to drum up more customers by vigorous promotion schemes, their most attractive lure has to do with stepped-up security measures. The airlines are reporting -- and promoting -- substantive improvements throughout their operations.

Pan American World Airways, for instance, has both reports tighter screening of all contract employees, including caterers, baggage handlers, refuelers and security forces themselves. Pan Am also is deploying plainclothes officers and trained dogs. More sophisticated screening machines are being installed, officials say, and airline personnel have been instructed to ask "friendly questions" of passengers as a way of establishing "traveler profiles." also has beefed up its security procedures for international flights and is asking more questions of its passengers.

These programs do seem to be more than public-relations gestures. Reports from passengers indicate consumer acceptance of the additional inconveniences. There is a risk that success -- or the absence of mishaps -- can lead to relaxation. Given the lingering uncertainties, however, air travelers are going to want continuing reassurances from the airlines that everything possible is being done to guard against the kind of horror that took place on Flight 847 a year ago.