AA 690 then AA 1524 at Philadelphia
Boston → Philadelphia → San Francisco
Timetable, Philadelphia time
07:37AA 690 from Boston at the gate
08:21AA 1524 to San Francisco leaves the gate
44 min apart on the timetable
The last days
AA 690 and AA 1524 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.