UA 3672 then AA 9912 at O'Hare
Richmond → Chicago → Richmond
Timetable, Chicago time
11:58UA 3672 from Richmond at the gate
07:30AA 9912 to Richmond leaves the gate
19 h 32 apart on the timetable, overnight
AA 9912 leaves 19 h 32 after UA 3672 arrives on the timetable: more than half a day, so not a connection we count.