Frontier Airlines Unsure of Impact from United's Flirtation with Bankruptcy.

Byline: Greg Griffin

Dec. 1--United Airlines' problems usually send passengers and revenues to Frontier Airlines, which has thrived in the shadow of its larger, often troubled rival in Denver.

But this time, as cash-bleeding United flirts with bankruptcy, Frontier officials aren't sure what will happen. Denver's low-cost airline is struggling with its own financial losses and could be hurt by a desperate and aggressive competitor in Chapter 11.

"We are getting ourselves prepared for whatever direction they may go," Frontier chief executive Jeff Potter recently told analysts. That means intensifying Frontier's focus on the basics: lowering costs and squeezing out more revenues in a tough market for air travel.

Chances are, Frontier's plan will succeed. Even under the hammer of bankruptcy, United is unlikely to reduce its expenses enough to challenge Frontier's cost advantage. And while airlines…