Shares of resurgent legacy carrier United Continental Holdings (NYSE: UAL) closed up more than 7% yesterday, the result of enthusiasm for an earnings report that isn't nearly as good as it looks.

And it does look good at first glance. Revenue surged 15% and adjusted earnings swung from a $0.60-per-share loss to a $0.44-per-share gain. United Continental's mainline load factor also improved a tenth of a percent to 82.7%. (Confused? Click here to get the skinny on all sorts of airline operating metrics.)

UAL also confirmed big orders with Airbus and Boeing (NYSE: BA). Despite the aircraft's well-documented problems, United Continental plans to acquire 25 of Boeing's fuel-efficient 787s. The implication? We have more than enough funding to expand and modernize our fleet, thank you very much.

Before you clap
Frankly, everything seems fine with UAL's report until you stack it up against what Delta Air Lines (NYSE: DAL) reported last week. Delta also booked a double-digit revenue gain and reversed prior-year losses in Q4. Yet its peer failed to impress the Street the way UAL has. The difference? Delta missed analyst expectations for profit.

Whether that actually means anything is debatable. Wall Street was embarrassingly low in projecting United Continental's Q4 profit, calling for just $0.23 a share. And that's not even the worst part.

(Clears throat) The aforementioned "worst part" ...
More galling is what the Street is choosing to pay attention to. I'll grant that Delta's results weren't great, but at least the carrier produced free cash flow ($52 million in the quarter, according to management's assertions).

United Continental can't make that claim. Not only did the carrier strip cash flow calculations out of its press release (a troubling change from Q3), but what little information we do have shows UAL's liquid resources dipped from $9.1 billion in the third quarter to $8.7 billion in Q4.

Something's burning at United, and it smells like cash. Should investors care? Use the comments box below to let us know what you think. You can also rate United Continental in Motley Fool CAPS.

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