UA 3902 then AA 2879 at O'Hare
Rio De Janeiro → Chicago → Charlotte
Timetable, Chicago time
17:01UA 3902 from Rio De Janeiro at the gate
11:40AA 2879 to Charlotte leaves the gate
18 h 39 apart on the timetable, overnight
AA 2879 leaves 18 h 39 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.