TheStreet'sAction Alerts PLUS Portfolio Manager Jim Cramer is keeping an eye on quarterly results from Lockheed Martin (LMT) - Get Report , released on Tuesday before the markets open.

Analysts expect the Bethesda, Md.-based aerospace giant to report fourth quarter earnings per share of $2.94 on sales of about $12.4 billion. During the same quarter last year, the company reported net income of $3.01 per share with revenue of $12.5 billion. Lockheed Martin is among the holdings of Cramer's charitable trust, Action Alerts PLUS.

"The defense stocks have been weak as of late," Cramer said. "It's actually not clear why because defense is probably, unfortunately, one of the long-term secular stories as everybody else rearms while the United States pulls back. We're focused too much on the U.S. pulling back and not enough on the worldwide rearmament."

Cramer will also be watching how helicopter maker Sikorsky is doing after being sold to Lockheed from United Technologies .

Lockheed Martin acquired Sikorsky for $9.1 billion last year. The helicopter giant provides choppers for each of the five arms of the U.S. military.

A recent Reuters report suggested the slump in oil prices could impact demand for helicopters, which are used in the oil drilling process. Oil prices are down over 20% year-to-date and 45% over the past 12 months, amid a glut of oil throughout global markets.

Shares of Lockheed Martin are down 6.7% since its most recent high on Nov. 24 of last year. Shares are lower by almost 1% since the start of the year, compared to the broad S&P 500's decline of over 7%.

Lockheed Martin has a trailing 12-month price-to-earnings ratio of roughly 18.4, according to data compiled by Bloomberg.