Northrop Grumman (NOC) reported on Wednesday a 9% drop in fourth-quarter profit, hurt primarily by lower sales in its largest segments and one-time costs.

The Los Angeles-based company posted net earnings of $376 million, or $1.27 a share, compared with $413 million, or $1.31 a share, in the same quarter last year.

Revenue for the provider of products and services in the aerospace, electronics, information and services and shipbuilding sectors was $8.6 billion, down slightly from $8.9 billion a year ago, missing the Street’s view of $8.8 billion.

Northrop Grumman CEO Wes Bush said the company had a “very good fourth quarter and a strong finish to 2010.”

“Operating income and cash generation exceeded our guidance for the year, demonstrating that across all our businesses, our employees are focusing on performance and building a track record of consistent execution,” he said.

Sales took a hit from a 10% drop in electronic systems, further impeded by a 4% decline in both its aerospace and information units. Despite the lower results however, its operating income in surged 66% to $178 million in information systems, and climbed 11% to $322 million in aerospace.

Looking ahead, the defense contractor expects to post revenue of $27.5 billion, and earnings in the range of $6.40 to $6.60 a share. The results reflect the anticipated divestiture of the company’s shipbuilding business in 2011.

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