AA 4775 then UA 5199 at O'Hare
Madison → Chicago → Denver
Timetable, Chicago time
06:14AA 4775 from Madison at the gate
08:30UA 5199 to Denver leaves the gate
2 h 16 apart on the timetable
The last days
AA 4775 and UA 5199 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.