AA 4997 then UA 5207 at O'Hare
South Bend → Chicago → Denver
Timetable, Chicago time
14:47AA 4997 from South Bend at the gate
21:00UA 5207 to Denver leaves the gate
6 h 13 apart on the timetable
The last days
AA 4997 and UA 5207 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.