AA 478 then AA 1422 at Phoenix
Philadelphia → Phoenix → Boston
Timetable, Phoenix time
13:05AA 478 from Philadelphia at the gate
16:52AA 1422 to Boston leaves the gate
3 h 47 apart on the timetable
The last days
AA 478 and AA 1422 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.