Gyo Obata, an architect whose designs included sports and entertainment arenas, airports and a presidential library, has died. His family says Obata died Tuesday in St. Louis at age 99. A cause of death was not announced. Obata was born in 1923 in San Francisco and earned a master’s degree at Cranbrook Academy of Arts in suburban Detroit. Obata, George Hellmuth and George Kassabaum opened Hellmuth, Obata & Kassabaum in 1955. St. Louis-based HOK is now among the world’s largest architecture and engineering firms. HOK’s notable designs include the Smithsonian’s National Air and Space Museum in Washington, Camden Yards baseball stadium in Baltimore, the Abraham Lincoln Presidential Library in Springfield, Illinois, and the Dallas-Fort Worth Airport.