Boeing Co. posted an unexpected 3 percent improvement in second-quarter net income on strong sales of commercial airplanes. The results surprised Wall Street and the company raised its earnings forecast for the year.

The results announced before the markets opened Wednesday eased investors' fears of an imminent slowdown in the company's defense unit, which produces Chinook helicopters and F-18s among many other aircraft models. They also highlighted strong growth in the company's commercial airplane unit which has been rapidly increasing the pace of production for some planes to meet demand.

Shares rose more than 2 percent in premarket trading.