DL 514 then DL 5704 at Boston
Phoenix → Boston → Washington National
Timetable, Boston time
06:23DL 514 from Phoenix at the gate
21:45DL 5704 to Washington National leaves the gate
15 h 22 apart on the timetable
DL 5704 leaves 15 h 22 after DL 514 arrives on the timetable: more than half a day, so not a connection we count.