AA 2950 then AA 2773 at Boston
Chicago O'Hare → Boston → Charlotte
Timetable, Boston time
09:37AA 2950 from Chicago O'Hare at the gate
12:55AA 2773 to Charlotte leaves the gate
3 h 18 apart on the timetable
Boston’s board gives an arrival time for only about 59% of its flights, so many days show no gate time.
The last days
AA 2950 and AA 2773 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.