(FORTUNE Magazine) – With fuel and labor costs spiking up fast, U.S. airlines are increasingly dependent on the lush revenues generated by full-fare business travelers. No one knows that better than Frank Lorenzo, 50, the onetime Wunderkind who soared to the top of the industry with Continental Airlines in the early 1980s only to crash as the decade came to a close. Continental's yield -- the revenue it received to fly a passenger one mile -- was one of the lowest in the industry last year. It generated just 11.2 cents, compared with 13.6 cents for Delta and 17.2 cents for USAir. With little hope of buffing up his image, Lorenzo sold most of his stake in Continental to Scandinavian Airlines System for about $30.5 million. Says Lee Howard, head of the Washington consulting firm Airline Economics Inc.: ''I really think the public misunderstood this guy, but he clearly had to go.'' With SAS chief Jan Carlzon at the controls, Continental could well rebound. It has strong hubs in Houston and Denver, as well as a prime launching pad in Newark, New Jersey, for transatlantic traffic. Lorenzo left Continental with the lowest labor costs among its competitors. Wages last year accounted for only 22.3% of costs at Continental, vs. 33.9% at United and 35% at American. Most important, Carlzon, 49, seems to have the right stuff to lure back business travelers. The charismatic Swede directed a dazzling turnaround at SAS, which is 50% owned by the governments of Sweden, Norway, and Denmark. Says John Pincavage, a director at the Transportation Group in New York, an airline investment banking firm: ''He inherited a don't-care culture and changed it into a do-care one.'' SAS lost $30 million in the two years before Carlzon took over in 1981. Last year, the company made $193 million on revenues of $4.6 billion.