Investment guru Jim Rogers says airline stocks have hit bottom around the world, making them a good buying opportunity.

High oil prices and the economic downturn hurt airline stock prices, Rogers writes on his Web site. But, "the volume of airline bankruptcies, lower capacity, and falling oil prices could make carriers prosper," he writes.

Rogers has launched a new airline stock index with Royal Bank of Scotland that contains 20 carriers to allow investors to better track the industry.

"The airline industry has been a nightmare for several years now, with dozens of airlines going bankrupt," Rogers notes. "That is often the sign of a bottom."

And what are the positive factors boosting the industry? "Capacity is shrinking at some airlines, while there will always be demand for seats," he writes.

"Many managements have now learned the lessons of the past decades."

The airline industry sagged as oil raced to a record high of $147 per barrel in July, but now the airlines' finances are improving.

Other experts agree with Rogers' bullish stance. "Our view going into the slow winter season, and the teeth of the economic weakness is be cautious but be prepared to buy airline stocks at bargain prices," Ray Neidl, an analyst with Calyon Securities, told Marketwatch.