AA 4447 then AA 955 at Boston
Lexington → Boston → Washington National
Timetable, Boston time
14:30AA 4447 from Lexington at the gate
17:35AA 955 to Washington National leaves the gate
3 h 05 apart on the timetable
Boston’s board gives an arrival time for only about 58% of its flights, so many days show no gate time.
The last days
AA 4447 and AA 955 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.