The airline's formula is lower fuel prices and more revenue for every mile that passengers fly.
United Continental Holdings Inc. said Thursday that third-quarter net income soared to $924 million, or $2.37 per share, compared with $379 million a year earlier.
But the Chicago company's shares fell in morning trading as analysts expressed disappointment with part of a fourth-quarter forecast. United said that revenue for every seat flown one mile, a closely watched figure in the airline business, would range between down 1 per cent and up 1 per cent.
Stifel, Nicolaus & Co. analyst Joseph DeNardi said the forecast surprised investors because Delta predicted flat to 2 per cent growth in the same figure. United said it was competing against a ticket-sales gain that it recorded in last year's fourth quarter.
In trading shortly after the opening bell, United shares were down $2.02, or 4.1 per cent, to $47.09.
Excluding special items, the company said it earned a record adjusted profit of $1.1 billion, or $2.75 per share, in the third quarter. Analysts, who usually exclude items, expected $2.70 per share.
Revenue rose 3.3 per cent to $10.56 billion, matching the forecast of analysts, according to a FactSet survey. It helped that so-called ancillary revenue rose 10.9 per cent as the average passenger paid more than $22 per trip in fees for things such as checked bags and more legroom.
Fuel spending fell 4.1 per cent, as the company paid $3.02 per gallon, a dime less than last summer. The figures included United Express regional flights.
United has been plagued by technology glitches that alienated customers; it struggled more than rivals to keep flying during bad weather; and it lagged other airlines when they turned solidly profitable. As recently as the first quarter of this year, United was still losing $609 million while key rivals set profit records.
But United earned a $789 million profit in the second quarter, beating Wall Street forecasts, and CEO Jeff Smisek said Thursday that the latest figures showed continued progress. He said the airline still has plenty of opportunities to increase profit margins "and improve the quality and efficiency of everything we do."