UA 4173 then AA 9912 at O'Hare
Richmond → Chicago → Richmond
Timetable, Chicago time
13:48UA 4173 from Richmond at the gate
07:30AA 9912 to Richmond leaves the gate
17 h 42 apart on the timetable, overnight
AA 9912 leaves 17 h 42 after UA 4173 arrives on the timetable: more than half a day, so not a connection we count.