Guardian Jet Center, an FBO and Avfuel dealer at Ontario International Airport, Calif., last month opened a 22,000-sq-ft hangar and adjoining 2,000-sq-ft office space. The company, which opened in November 2002, now plans to build a new executive terminal in between the new hangar and an original hangar. Guardian Jet Center is also home of Guardian Air Services, the company’s charter operation, and other aircraft services.