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What: United Continental Holdings (NYSE: UAL) nosedived 10% in intraday trading today after disclosing disappointing revenue expectations and a $110 million charge for the second quarter.  

So what: The company expects an 8.3% to 9.3% increase in consolidated passenger revenue per available seat mile in the second quarter, below analysts' expectations of a double-digit gain. There will also be a $110 million charge stemming from a change in the way mileage credits sold to Chase Bank are accounted for.

Now what: According to UBS, that means the $1.54 consensus EPS estimate for the quarter is about $0.30 too high. United Continental said demand was in line with its expectations, but a transatlantic joint venture revenue-sharing agreement and other items are affecting revenue. Disruptions related to the tragedy in Japan and sky-high oil prices are also causing turbulence for airlines. American Airlines' parent company AMR (NYSE: AMR) lowered its revenue forecast by $60 million, citing weather-related disruptions and the tragedy in Japan.

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Fool contributor Cindy Johnson does not own shares of any company named above. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.