WASHINGTON — U.S. factory orders rose strongly in July on the biggest jump in demand for autos in more than eight years and a surge in commercial airplane orders. The increase suggests supply chain disruptions created by the Japan crisis are easing.

The Commerce Department says factory orders climbed 2.4 percent, the largest increase since March. Orders for motor vehicles and parts rose 9.8 percent, the largest one-month gain since January 2003.

The increase follows a decline of 0.4 percent in June, which stoked fears the country could fall back into a recession.

Manufacturing has been one of the leading sectors since the recession officially ended two years ago. But higher energy prices and a parts shortage caused by the Japanese natural disasters slowed activity this spring.