AA 6486 then OO 391 at O'Hare
Detroit → Chicago → Detroit
Timetable, Chicago time
17:29AA 6486 from Detroit at the gate
14:30OO 391 to Detroit leaves the gatealso UA 391
21 h 01 apart on the timetable, overnight
OO 391 leaves 21 h 01 after AA 6486 arrives on the timetable: more than half a day, so not a connection we count.