AA 6486 then AA 3974 at O'Hare
Detroit → Chicago → Harrisburg
Timetable, Chicago time
17:29AA 6486 from Detroit at the gate
10:35AA 3974 to Harrisburg leaves the gate
17 h 06 apart on the timetable, overnight
AA 3974 leaves 17 h 06 after AA 6486 arrives on the timetable: more than half a day, so not a connection we count.