(FORTUNE Magazine) – Is Boeing, arguably the flagship of America's global competitiveness, following IBM and General Motors into sputtering decline? A tempest in the airline industry and an overstuffed cargo of costs are slowing the nation's No. 1 exporter. Orders are tumbling so fast (see chart) that sales could plummet from $30 billion in 1992 to $23.5 billion in 1995, says Jerry Cantwell, a security analyst with Wertheim Schroder. The stock price has fallen from almost $62 a share in 1990 to $38. Even in hometown Seattle, citizens call Boeing the Lazy B, a slap at its plodding bureaucracy. As that moniker implies, Boeing's problems aren't all cyclical. Yes, the commercial aircraft market should rebound strongly in the middle to late 1990s, driven by growing air travel in Asia and South America as well as by revived demand from U.S. carriers replacing old fleets (see facing page). Boeing appears well positioned to profit: It still holds an impressive 56% of the world market. But keeping that huge share will get tougher. Squeezed by fare wars, airlines are pressing manufacturers to cut prices and speed development. Boeing's few competitors say they can do just that, and new rivals threaten to spring up. Airbus, the heavily subsidized European consortium, is invading Boeing's stronghold, the U.S. market. In a nose cone to nose cone battle last year, Airbus captured a $2.4 billion order for 100 midsize planes from United Airlines, once a loyal Boeing customer. That's a skirmish compared with the carnage ahead. Two of Boeing's biggest sources of profit are its lucrative near monopoly in jumbo jets -- the 747-400, for example -- and its dominance in small, 130-seat planes like the 737-300. Airbus vows to develop new aircraft that will compete in both of those market segments by the middle to late 1990s. Embattled McDonnell Douglas is seeking an Asian or European partner to share the costs of building its own jumbo, the MD-12. And Taiwan and China both have multibillion-dollar plans to enter the commercial aircraft industry by 2000. ! But unlike IBM or GM before the fall, Boeing seems to see the perils ahead and has set ambitious goals to keep its lead. CEO Frank Shrontz promises to lower total costs 25% to 30% over the next five years and reduce aircraft delivery times from an average 14 months to six. Boeing is already making impressive strides in reducing stocks: A large manufacturing division saved nearly $100 million last year by paring inventories about $1 billion. It's too early to tell whether Boeing will win its war on costs. ''No longer having an assured market share has our adrenaline flowing,'' claims Ronald Woodard, the executive in charge of the division that makes the 737 and 757. Boeing is still above the clouds -- but it will have to work harder than ever to maintain altitude.

CHART: NOT AVAILABLE CREDIT: FORTUNE CHART CAPTION: Market share is holding. . . but orders are down. . . and share price has nose-dived