Orders to U.S. factories for durable goods rose in September as the biggest increase in demand for machinery in 18 months offset weakness in commercial aircraft and autos, the government reported Wednesday. The Commerce Department said orders for durable goods-expensive manufactured items expected to last at least three years-rose 1 percent last month, matching economists' expectations. Excluding transportation, durable-goods orders rose 0.9 percent, slightly better than economists had expected. The overall increase was led by a 7.9 percent jump in machinery orders, the best performance since an 8.5 percent surge in March 2008. Orders for non-defense capital goods-considered a gauge of business investment plans-rose 2 percent, the strongest advance since June. Demand for transportation equipment rose 1.1 percent after a 9.1 percent drop in August. Orders for defense aircraft rose 12.5 percent in September, offsetting a 2.1 percent decline in demand for commercial aircraft and a 0.1 percent drop in orders for autos and auto parts. Orders for primary metals rose 0.3 percent, and orders for computers and related products rose 0.4 percent last month. September's rise in durable-goods orders followed a 2.6 percent drop in August and a 4.8 percent increase in July, indicating that any recovery in the manufacturing sector will be uneven. The second advance in three months for durable-goods orders is a hopeful sign for the sector, which has led the early stages of the economic recovery. But many economists are concerned that demand could weaken in the coming months as various government stimulus programs end. --SPA