UA 3902 then AA 3974 at O'Hare
Rio De Janeiro → Chicago → Harrisburg
Timetable, Chicago time
17:01UA 3902 from Rio De Janeiro at the gate
10:35AA 3974 to Harrisburg leaves the gate
17 h 34 apart on the timetable, overnight
AA 3974 leaves 17 h 34 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.