Gulfstream Aerospace, a maker of business-jet aircraft, announced Monday that it is expanding operations in Georgia by adding more than 1,000 jobs and investing at least $500 million. Gulfstream's seven-year plan calls for expanding its jet production and maintenance facilities at the Savannah-Hilton Head International Airport and renovating several existing facilities on its main Savannah campus. New positions will include production engineering and support technician jobs, the company announced. It is Gulfstream's second major expansion on Georgia's Atlantic coast in half a decade.