F9 2021 then DL 2073 at Detroit
Philadelphia → Detroit → Washington National
Timetable, Detroit time
00:05F9 2021 from Philadelphia at the gate
21:55DL 2073 to Washington National leaves the gate
21 h 50 apart on the timetable
DL 2073 leaves 21 h 50 after F9 2021 arrives on the timetable: more than half a day, so not a connection we count.