UA 6104 then AA 492 at O'Hare
South Bend → Chicago → Cancún
Timetable, Chicago time
19:00UA 6104 from South Bend at the gate
10:05AA 492 to Cancún leaves the gate
15 h 05 apart on the timetable, overnight
AA 492 leaves 15 h 05 after UA 6104 arrives on the timetable: more than half a day, so not a connection we count.