UA 3922 then AA 1632 at O'Hare
Savannah → Chicago → Tucson
Timetable, Chicago time
02:36UA 3922 from Savannah at the gate
20:56AA 1632 to Tucson leaves the gate
18 h 20 apart on the timetable
AA 1632 leaves 18 h 20 after UA 3922 arrives on the timetable: more than half a day, so not a connection we count.