UA 503 then DL 703 at Boston
Newark → Boston → Washington National
Timetable, Boston time
09:17UA 503 from Newark at the gate
18:00DL 703 to Washington National leaves the gate
8 h 43 apart on the timetable
The last days
UA 503 and DL 703 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.