AA 9921 then AA 301 at O'Hare
Phoenix → Chicago → Milwaukee
Timetable, Chicago time
16:00AA 9921 from Phoenix at the gate
19:47AA 301 to Milwaukee leaves the gatealso UA 301
3 h 47 apart on the timetable
The last days
AA 9921 and AA 301 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.