The exhaust from the engines of a commercial aircraft create the illusion of a solar flare as it flies in front of the sun in Wilmington, Delaware, May 18, 2007. (REUTERS / Tim Shaffer)

Many U.S. airlines' shares showed resiliency even as their global counterparts took another hit on Tuesday amid warnings of steep falls in traffic in wake of the swine flu outbreak.

Among U.S. carriers, American parent AMR Corp and US Airways Group climbed as much as 2 percent. Industry leader Delta Air Lines fell more than 2 percent. The AMEX airlines index <.XAL> was off 0.2 percent in afternoon New York trading.

Cruise and hotel operators also bounced back, with Carnival Corp and Royal Caribbean Cruises Ltd up 2 percent to more than 4 percent.

The swine flu was expected to cause customers to cancel their travel plans, sending shares down in double-digit percentages on Monday, but a day later, it appeared travelers were largely keeping their plans.

As more news comes out on swine flu, it's more apparent to investors that it's a localized thing, said Jim Corridore, an analyst with Standard & Poor's Equity Research. It's mostly in Mexico where at least U.S. airlines get a very small percent of their revenues. And it's likely to be of short-term duration.

Matthew Jacob, an analyst with Majestic Research, said the Monday sell-off could have created a buying opportunity for U.S. investors.

Stocks took a big hit yesterday and they're not fully recovering that amount and there's still some risk out there, he said.

But I do think that there's a feeling that some of the (swine flu) concerns may be a little bit overblown in the travel industry, he added. It does not seem that it's going to stop the recovery that we had been seeing elsewhere in the industry.

Swine flu has killed at least 149 people in Mexico.

In Europe and Asia, airline stocks posted a second -- albeit more modest -- day of declines following comments made by Geneva-based International Air Transport Association that a possible pandemic from swine flu could bring more pain.

Anything that shakes the confidence of passengers has a negative impact on the business. And the timing could not be worse given all of the other economic problems airlines are facing, IATA said in its monthly traffic statement.

British Airways and Air France-KLM -- a combination of two networks that collectively have the largest European exposure to Mexico -- lost about 5 percent and 2 percent, respectively.

In Asia, Hong Kong's Cathay Pacific <0293.HK>, which bore the brunt of the SARS crisis in 2003, closed down 0.9 percent after sharp earlier falls, and Air China <0753.HK> fell 7 percent.

Stone Lin, an airline analyst with Yuanta Securities in Taiwan, said the flu outbreak could dim hopes for summer travel.

The summer months of July-September are typically the peak season for most airlines, with most bookings beginning right now, the analyst said.

With sentiment so weak, and worsened by the swine flu issue, it's unlikely anyone is going to go rushing to book holidays or corporate travel, which means the second half of this year won't be pretty for most airlines, he added.

IATA, which represents 230 carriers, said airlines could lose $4.7 billion this year before any impact from swine flu.

But Michael O'Leary, the head of leading European low-cost airline Ryanair , sounded a contrarian note.

Are we going to die from swine flu? No. Are we in danger of SARS? No. Foot and mouth disease? No. Will it affect people flying short-haul flights around Europe this summer? Thankfully, no, he said.

During the SARS outbreak, which began in China, airline traffic in Asia halved, and airline stocks tumbled 25 percent or more.

Most industry watchers, however, said it was still too early to say how big the swine flu risk could be to airlines this time.

overall situation is weaker now ... because there are two headwinds the
airline industry is facing: one is the global recession and now this
outbreak of swine flu, said Daphne Roth, analyst at ABN Amro private

But she added the current situation was also different from SARS, as information about the illness is coming out faster.

is a lot of fear out there right now and I think we've got to see if it
gets much worse or the same or better over the next few weeks, said
Clay Jones, chief executive of Rockwell Collins, a U.S. supplier of parts to Boeing Co and EADS unit Airbus.

Mexico stays the center of attention, I'm not overly concerned, Jones
added. If it spreads widely in the United States, obviously that's a
much different situation.

(Writing by Tim Hepher in Paris, Doug
Young in Taipei and Karen Jacobs in Atlanta; additional reporting by
Reuters bureaus across the world; editing by Will Waterman and Patrick