Defense titans returned to growth-mode in the second quarter, and Northrop Grumman (NOC -0.19%) was among the companies leading the charge.

Shares of Northrop gained 11.1% in July, according to data provided by S&P Global Market Intelligence, after the company reported better-than-expected second-quarter results.

Strong top- and bottom-line growth

Northrop Grumman is one of the world's premier defense companies, with a portfolio of aviation, space, and missiles that are sold to the U.S. government and allies around the world. But defense is a long-cycled business, and new programs can take years to generate revenue, creating a recent lull in Northrop shares.

The company's Q2 results provided indications that Northrop Grumman is back in growth mode, and investors reacted by rallying into the shares. Northrop earned $6.36 per share in the quarter on revenue of $10.2 billion, outpacing Wall Street's $5.93 per share on $10 billion in sales estimate.

Northrop grew sales by 7% in the quarter and operating income by 13%, reporting $1.1 billion in free cash flow during the three-month period. The company also raised its full-year earnings and revenue guidance, an indication management expects the momentum to continue for the remainder of 2024.

"Our diverse portfolio includes capabilities in high demand and we have invested to create capacity and drive productivity to deliver differentiated capabilities for our customers," CEO Kathy Warden said in a statement. "We are laser focused on performance and continue to expand profitability through the deliberate actions we are taking."

Northrop also clarified that government-held options to buy the new B-21 bomber that were negotiated in 2018 contained cost escalators and are therefore expected to be profitable. Northrop shares have been under pressure on fears that spiraling post-pandemic supply-chain costs would change the economic calculus of Northrop's most important military platform, making the bomber an albatross on the company's balance sheet for years to come.

Is Northrop Grumman stock a buy?

Although defense stocks tend to come into the spotlight during times of geopolitical uncertainty, investors would be wise to ignore the headlines and focus on fundamentals. Large-system integrators like Northrop are developing decade-plus platforms regardless of what is going on in the world and tend to be somewhat insulated from outside forces.

Northrop has been in a period of investment as the B-21 and the separate Sentinel program are under development. It appears that period is nearing completion, and if so, growth should be back on the menu.

Northrop does have some uncertainty in the quarters to come, with the initial B-21 deliveries expected to be break-even at best. Arguably the company's archrival Lockheed Martin, which also exceeded quarterly expectations and was up 16% for the month, should be able to outperform up ahead thanks to more certainty surrounding its F-35 program and Lockheed's greater success winning foreign sales order.

But for those looking for reliable ballast in their portfolio, Northrop Grumman is an intriguing option.