Gulfstream Aerospace this week celebrated the 25th anniversary of the first flight of the Gulfstream IV, which the Savannah, Ga.-based manufacturer said is “the best-selling” large-cabin, long-range business jet in the world. On Sept. 19, 1985, three months ahead of schedule, the aircraft took off from Savannah (Ga.) International Airport, just eight days after it was rolled out at the manufacturer’s headquarters in Savannah. Lee Johnson and Ted Mendenhall were the pilot and copilot, respectively, for the one-hour maiden flight. “The GIV was the aircraft that launched a thousand Gulfstream aircraft,” said Gulfstream president Joe Lombardo. “It formed the foundation for designing and building the G300, G400, G350 and G450. The aircraft’s first flight was a milestone and turning point for the company.” More than 520 of the 536 jets produced in the GIV series are still in operation, the company said. “I believe it became popular because it was on the leading edge of globalization,” said longtime Gulfstream employee Jim Gallagher, who is now director of the large and mid-cabin sustaining program. “Halfway through its production run, the GIV became the preferred tool of global business jet travelers. Companies relied on it to travel worldwide; it helped push global commerce.”