(FORTUNE Magazine) – He has a reputation for saving failing airlines -- first Republic, then Tiger International -- by persuading labor to submit to his cost slashing. But United Airlines' new chief executive, Stephen Wolf, 46, has felt little pain himself. Kirk Faupel, the pilots' union chief at Republic, estimates that Wolf ''profited by over $3.5 million'' in less than 23 months there. In December, just 16 months after being recruited to save the Flying Tigers cargo line, Wolf flew off laden with lolly. Director Saul Steinberg says Wolf took $10 million in stock options and walked away from $10 million more. United will make up the difference with stock options and another compensation deal the airline won't describe. Even Wolf's detractors say United is getting its money's worth. A 21-year industry veteran, he did tours at American, Pan Am, and Continental before joining Republic. ''He's got a better grasp of the details of the business ; than anyone I've seen in 25 years,'' says Frank Maguire, the pilots' union chairman at Tiger. Thanks to Wolf, a 6-foot-6 workaholic bachelor, the cargo line now boasts an operating margin of 13%, nearly double that of American. For the first nine months of 1987, Tiger reported earnings of $45 million, vs. a loss of $55 million a year earlier. ''He's a driven man,'' says Steinberg. ''He has no hobbies whatsoever. He wouldn't be a fun date, I don't think.'' Nor is he a fun boss, some say. Contends Paul Phillips, vice chairman of the Tiger pilots' union: ''He doesn't like us. He views us as another fixed expense, like food and fuel. If he could get microchips to sit in the seat, fine. Those United boys are in for a real fight.'' Wolf will probably take a more conciliatory stance at United. Unlike Republic and Tiger, United is far from bankruptcy. Acquaintances say that at United Wolf has realized a life's dream of heading a major passenger airline. ''He thinks he's the best in the business, and he probably is,'' says Maguire of Tiger. ''When you think you're the best, you want to play Carnegie Hall. United is his Carnegie Hall.''