AIRLINES

Northwest Changes Cut-Rate European Fare Plan: Major U.S. airlines are studying a move by Northwest Airlines to extend to Feb. 9 what had been a Dec. 31 deadline to buy cut-rate European fares. Northwest officials said an earlier statement by the airline that the final purchase date had been advanced to March 15, 1993, was incorrect. The non-refundable fares offer savings as high as 43% on $498 round-trip fares from Los Angeles and Frankfurt, Germany, for flights through March 31, 1993, compared to the normal $878 round-trip super saver fare. A Saturday night stay is needed and tickets must be bought at least 14 days ahead of travel.