Malaysian airline AirAsia expects stronger passenger growth next year as it adds new routes and planes, saying the darkening economic outlook will boost demand for its budget flights.

Southeast Asia's largest low-cost airline plans to add nine new aircraft in 2009 to its existing fleet of 72 planes, said chief executive Tony Fernandes.

"I am very optimistic. I mean you just saw easyJet came out with some very aggressive numbers on passenger growth, and Europe is in a much worse position than Asia," he told reporters.

The British low-cost airline said on Monday passenger volumes grew 20 percent in September despite the global credit crunch triggered by the US mortgage crisis, but it also warned of slowing demand in winter months.

"I am not saying that the market won't shrink, but I am saying that AirAsia is in a strong position to capitalize on whatever economic situation," said Fernandes.

"If there is a slowdown, people who used to fly on other airlines may start flying on us. Business would still go on, we are not in an armageddon situation," he added.

AirAsia, which also has operations in Thailand and Indonesia, reported a rise of 20 percent in second-quarter passenger volumes to 2.82 million, company data showed.

Asked about newspaper reports that he planned to take AirAsia private and de-list the company from Bursa Malaysia, Fernandes declined to comment.

"An appropriate statement will be made by AirAsia and Tune Air (its major shareholder) when it is appropriate," he said.