Sept 4 (Reuters) - United Airlines said on

Thursday that it would expand its winter schedule and add

flights to 15 cities including Fort Lauderdale, Orlando, and Las

Vegas.

United's move aims to cash in on flights operated in key

regions by Spirit Airlines, days after the no-frills pioneer

filed for bankruptcy protection for the second time in a year.

"If Spirit suddenly goes out of business it will be

incredibly disruptive, so we're adding these flights to give

their customers other options if they want or need them," said

Patrick Quayle, United's senior vice president of Global Network

Planning and Alliances.

The new flights will begin in January, with tickets on sale

later on Thursday.