AA 3521 then UA 5901 at O'Hare
Bloomington-Normal → Chicago → St Louis
Timetable, Chicago time
06:14AA 3521 from Bloomington-Normal at the gate
15:20UA 5901 to St Louis leaves the gate
9 h 06 apart on the timetable
The last days
AA 3521 and UA 5901 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.