AA 4740 then UA 3376 at O'Hare
Norfolk → Chicago → St Louis
Timetable, Chicago time
19:55AA 4740 from Norfolk at the gate
11:00UA 3376 to St Louis leaves the gate
15 h 05 apart on the timetable, overnight
UA 3376 leaves 15 h 05 after AA 4740 arrives on the timetable: more than half a day, so not a connection we count.