When past recessions have hit, one of the first sectors to feel the pinch has been transportation — both commercial and passenger.

        Freight companies are dependent on manufacturers, which normally scale back production of goods that need transporting in a recession. And passenger compa nies are dependent on extra income that dries up during a recession.

        That means that once again, the transportation industry is especially vulnerable to a slowdown, said Aaron J. Gellman, director of the Transportation Center at Northwestern University,

        who offers one caveat: A slowdown probably won't stop growth in transportation altogether.

        “It definitely will slow the growth rate and demand, but it would take deep cuts to really stop it, as big as the industry has gotten,” Mr. Gellman said. “Still, the smaller companies that have grown up during the good times, especially highway carriers, will have a hard time surviving.”

        Airlines, which have seen record growth and demand over the past five years, could be especially vulnerable, since they rely so heavily on discretionary income from both individuals and companies.

        And airlines are currently struggling with labor unrest, meaning that demand may drop off at the same time that workers are asking for large pay raises to take advantage of the recent growth.

        But one Wall Street analyst said recent changes in the industry — such as a focus on earnings instead of market share, the emphasis on code sharing and alliances, the influence of the Internet and a plane shortage — could actually make airlines more valuable in a recession.

        “If the airlines show themselves to be profitable during a recession, then the market will find them even more valuable,” said Julius Maldutis, analyst for CIBC World Markets in New York. “I believe they can do it given the changes in management philosophy, and they won't see the same kind of financial distress as in the past.”

Are we headed for a recession?
  • Manufacturing: Excess inventory a danger
  • Wall Street: Not all stocks off
  • Interest rates: Housing market may stay strong
  • Retail sales: Falling confidence could curtail spending
  • Media: Newspapers most vulnerable to downturn
  Transportation: Trucks, airlines may feel pinch
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