NEW YORK (CNN/Money) - The financially troubled parent of United Airlines posted its smallest loss since the Sept. 11 terrorist attack, beating Wall Street's expectations, but the company saw its month-to-month improvement stall and said it sees a more difficult liquidity position ahead without federal help.

UAL Corp., the world's No. 2 airline holding company, lost $392 million, or $6.99 a share, excluding special items in the second-quarter. While that was up from the $292 million, or $5.50 a share, it lost in the year-earlier period, it's better than the analysts' consensus forecast of a loss of $7.13 a share from earnings tracker First Call.

Shares of UAL (UAL: down $0.85 to $6.68, Research, Estimates) lost about 11 percent in early trading Friday.

Including special items, the company posted a net loss of $341 million, or $6.08 a share, down from the net loss of $365 million, or $6.87 a share, a year earlier.

Revenue fell 18.6 percent to $3.79 billion. Miles flown by passengers fell 14.7 percent to 27.9 billion, and while schedule cuts left United planes a bit closer to capacity than a year earlier, the average amount passengers paid per mile, a measure of fares, fell 7 percent to 11.4 cents.

"This second-quarter loss demonstrates clearly that United continues to suffer from the weak revenue environment since Sept. 11," CEO John Creighton said. "The month-to-month improvements we've seen so far this year have stalled. In fact, our June unit revenue performance is slightly worse than it was in May."

United said it ended the quarter with a cash balance of $2.7 billion, off $200 million from the end of the first quarter. It had negative cash flow of less than $1 million a day in the second quarter, an improvement from the less than $5 million daily cash burn rate in the first quarter.

But the company expects its cash burn to be worse in the third quarter and to further deteriorate in the fourth quarter due to seasonal trends. It also said it has nearly $900 million in debt coming due near the end of the year and is concerned about its ability to refinance it due to lack of access to capital markets. The company is seeking $1.8 billion in federal loan guarantees to deal with its cash problems.

In other airline financial results, America West Holdings Corp., the nation's No. 8 airline, posted a second-quarter loss about half of Wall Street forecasts.

The company reported it lost $9.9 million, or 29 cents a share, excluding special items, an improvement from the $15.3 million, or 46 cents a share, it lost on a comparable basis a year earlier. First Call had forecast a loss of 58 cents a share.

Including special items, including additional federal assistance it received in the period, the company posted a net loss of $8.5 million, or 25 cents a share, an improvement from the net loss of $42.5 million, or $1.26, a year earlier. Revenue fell 7.3 percent to $544.1 million.

Shares of America West (AWA: up $0.07 to $2.45, Research, Estimates) gained about 5 percent early Friday following the report.