MASON CITY, Iowa (WLS) -- Plane headed to Chicago from South Dakota had to make an emergency landing in Mason City, Iowa.The American Eagle jet bound for O'Hare made an unexpected landing at the Mason City Municipal Airport on Tuesday. The flight was operated by Envoy Air and landed in Mason City around 1 p.m.A passenger says there was smoke coming from the cockpit.According to a spokesperson for Envoy Air, the plane had a maintenance issue.The plane, which originated in Sioux Falls, South Dakota, was evacuated.There were 45 passengers on board and three crewmembers aboard and no reported injuries. Envoy Air says there are working on getting a replacement plane and crew to bring the passengers to Chicago.