AA 1428 then AA 880 at Philadelphia
Atlanta → Philadelphia → Chicago O'Hare
Timetable, Philadelphia time
09:47AA 1428 from Atlanta at the gate
10:40AA 880 to Chicago O'Hare leaves the gate
53 min apart on the timetable
The last days
AA 1428 and AA 880 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.