AA 1252 then UA 2817 at Miami
Philadelphia → Miami → Newark
Timetable, Miami time
08:59AA 1252 from Philadelphia at the gate
13:52UA 2817 to Newark leaves the gate
4 h 53 apart on the timetable
The last days
AA 1252 and UA 2817 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.