 A severe downdraft, associated with a nearby thunderstorm, was cited as the cause.On July 23, 1973, Ozark Air Lines Flight 809 was operated by one of the companys Fairchild-Hiller FH-227s, registration N4215.The flight was scheduled to go from Nashville, Tennessee, to St. Louis, Missouri, with four intermediate stops at Clarksville, Tennessee; Paducah, Kentucky; Cape Girardeau, Missouri; and Marion, Illinois.