AA 3521 then OO 9908 at O'Hare
Bloomington-Normal → Chicago → Milwaukee
Timetable, Chicago time
06:14AA 3521 from Bloomington-Normal at the gate
12:00OO 9908 to Milwaukee leaves the gate
5 h 46 apart on the timetable
The last days
AA 3521 and OO 9908 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.