“This crisis is resizing and reshaping the industry,” the group’s chief executive, Giovanni Bisignani, said in a conference call from the group headquarters in Geneva. He predicted revenue would fall 12 percent, or $62 billion, in 2009  double its contraction after the Sept. 11, 2001, attacks. That is chiefly because airlines are suffering from sharp declines in the two areas from which they derive most of their revenue: first- and business-class passenger traffic and freight.

Image This crisis is resizing and reshaping the industry, says Giovanni Bisignani of the International Air Transport Association. Credit... Christine Muschi/Reuters

High-end passenger traffic fell 16.7 percent in January and cargo dropped 23.2 percent.

While the Asia-Pacific region will be the worst hit, forecast to lose $1.7 billion this year, airlines in North America were expected to turn a $100 million profit. Those carriers have been quick to reduce capacity in line with an expected 7.5 percent drop in demand, and they avoided the pain of misjudged oil hedging contracts that left other carriers exposed when prices fell last year.

“Over the past 15 months we suspended nearly 40 airlines. The reason? They couldn’t pay their bills,” Mr. Bisignani said, referring to the 500 carriers in the association’s fare settlement system, although most of the suspended airlines were small.

Airlines are experiencing difficulty in obtaining credit from banks to finance the purchase of new aircraft. The group predicted that the world’s airline fleets would absorb only 700 jets from Boeing and Airbus together by 2011, compared with 1,400 scheduled for delivery this year alone.