(This article about world airlines appeared in the Huffinton Post, March 24, 2009.  editor)

GENEVA — World airlines will lose $4.7 billion this year due to the economic crisis, while revenues will drop by more than after the Sept. 11, 2001 terrorist attacks in the U.S., a major industry association predicted Tuesday.

The revised loss estimate, nearly double the previous forecast issued in December, reflects "the rapid deterioration of the global economic conditions," said the International Air Transport Association.

"The state of the airline industry today is grim," said IATA CEO Giovanni Bisignani. "Demand has deteriorated much more rapidly with the economic slowdown than could have been anticipated even a few months ago."

Revenues are expected to fall by $62 billion, or 12 percent, to $467 billion, the association said.

"Resizing the industry will be much tougher than the adjustments we saw after 9/11 or SARS," Bisignani said.