TWA to Offer Two-for-One Fares: Trans World Airlines Inc. said its new ticket sale for domestic and international routes will allow passengers to fly with a companion at no extra charge. To qualify, travelers must purchase their tickets by Friday and travel between Sept. 13 and Jan. 31. The trip must include a Saturday night stay and holidays are blacked out. Major airlines often match major fare sales by competitors. All domestic routes and flights on Trans World Express, a TWA subsidiary, are included in the sale, the carrier said.