5X 610 then AA 9956 at O'Hare
Philadelphia → Chicago → Washington National
Timetable, Chicago time
04:215X 610 from Philadelphia at the gate
09:15AA 9956 to Washington National leaves the gate
4 h 54 apart on the timetable
The last days
5X 610 and AA 9956 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.