Amid tightening defense spending and uneven results from its Orlando units, Lockheed Martin Corp. posted lower fourth-quarter profit and sales Thursday, even as the defense giant said it expects to weather the military spending downturn in good shape.

Bethesda, Md.-based Lockheed earned $569 million, or $1.73 a share, on sales of $12.1 billion in the quarter, down 18.5 percent and 1 percent, respectively, from the same quarter last year. For all of 2012, Lockheed earned $2.75 billion on sales of $47.2 billion, up 3.4 percent and 1.5 percent, respectively.

The company's fourth-quarter sales beat the consensus Wall Street forecast of $11.2 billion, but fell short of the profit estimate of $1.82 per share, according to Thomson Reuters' analyst survey.

Lockheed said fourth-quarter sales and operating profits fell in its aeronautics, space systems and information systems, but increased in the missiles and fire control and mission systems/training sectors -- which together employ about 6,000 in Central Florida. It also cited increased costs in pension contributions and severance costs related to work force reductions.