By the late 1950s, airplanes were a fairly common sight over Des Moines, but not quite like this. On January 29, 1957, Roy Soderquist took a Cessna 172 from his flight instructor and spent the next several hours flying low over downtown Des Moines. He managed a crash landing in a field, with little injury to himself and the plane. Charges against him were dismissed.
The sources for this information are the Des Moines Register, 1/30/1957; and Des Moines Tribune 1/29/1957.