AA 6344 then UA 5194 at O'Hare
Lexington → Chicago → Sioux City
Timetable, Chicago time
06:08AA 6344 from Lexington at the gate
00:00UA 5194 to Sioux City leaves the gate
17 h 52 apart on the timetable, overnight
UA 5194 leaves 17 h 52 after AA 6344 arrives on the timetable: more than half a day, so not a connection we count.