Lockheed Martin Corp.’s shares dropped as much as 4 percent after the company reported first-quarter revenue of $11.06 billion, which missed analysts’ forecasts of $11.23 billion for the period due to lower-than-expected sales.

The U.S. defense contractor’s net earnings from continuing operations fell to $763 million from $806 million in the year ago period. Adjusted earnings per share was reported as $3, topping Wall Street forecasts of $2.79 per share.

Net earnings from continuing operations were impacted by a $120 million charge for a loss program to design, integrate and install an integrated air missile defense system for an international customer.

“While our net earnings were impacted by certain adjustments, we increased our outlook for full year cash from operations by $300 million to at least $6.0 billion and we continue to position the company to deliver outstanding value to customers and shareholders,” said president and CEO Marillyn Hewson.

Lockheed lowered its full year earnings outlook to between $12.15 per share and $12.45 per share from its previous view between $12.25 per share and $12.55 per share.

The defense contractor’s shares, which have climbed nearly 11 percent so far this year, 4 percent in pre-market trading to $265.32 Tuesday morning after the announcement. They were trading at $268.36, down $7.85, in midday Tuesday trading.

The Securities and Exchange Commission filing can be found here.