AA 4504 then UA 1369 at O'Hare
South Bend → Chicago → Washington National
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
18:00UA 1369 to Washington National leaves the gate
23 h 25 apart on the timetable, overnight
UA 1369 leaves 23 h 25 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.