For the first time in five years, worldwide deliveries of general aviation airplanes declined in 2008 (dragged down by slumping piston deliveries), but business jet and turboprop shipments increased by double digits and industry billings climbed to $24.8 billion, a 13.4-percent increase over 2007, according to an annual report released this morning by the General Aviation Manufacturers Association (GAMA). The group attributed the increase in billings to order backlog, reflecting the filling of orders placed for turboprops and business jets during 2006 and 2007. Shipments, meanwhile, dropped 7.1 percent from 4,272 in 2007 to 3,969 last year, and GAMA chairman Mark Van Tine acknowledged that the GA manufacturing industry is feeling a significant impact from the slowing worldwide economy. The piston airplane segment took the biggest hit last year, with 2,119 units delivered, compared with 2,675 airplanes in 2007. Turboprops experienced the strongest growth last year, with 535 airplanes shipped, a 17-percent rise from the 459 aircraft in 2007. Business jet shipments reached a new plateau last year at 1,315 delivered, up 15.6 percent over the previous year’s 1,138. Of the total number of aircraft manufactured last year, most–3,252–were shipped to North America. Thirty-eight went to South America, 576 to Europe and 103 to the rest of the world.