America West Cuts Fares: America West Airlines cut its fares by as much as 30% in an effort to stimulate travel during the winter months. The non-refundable tickets must be purchased seven days in advance of departure and require one Saturday night stay. The lowest fares are available for flights on Tuesdays, Wednesdays and Saturdays. The lowest round-trip fare between Los Angeles and New York would be $368. Tickets must be purchased by Jan. 21 and travel completed by March 10. Separately, Virgin Atlantic Airways said it is offering a one-way fare between Boston and London for $93, valid between Jan. 10 and Feb. 21, 1993, with round-trip tickets available for $193 each.