AA 2124 then AA 1366 at O'Hare
Indianapolis → Chicago → Denver
Timetable, Chicago time
06:01AA 2124 from Indianapolis at the gate
11:54AA 1366 to Denver leaves the gate
5 h 53 apart on the timetable
The last days
AA 2124 and AA 1366 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.