DL 3858 then UA 4500 at Detroit
Elmira → Detroit → Washington
Timetable, Detroit time
07:35DL 3858 from Elmira at the gate
19:45UA 4500 to Washington leaves the gate
12 h 10 apart on the timetable
UA 4500 leaves 12 h 10 after DL 3858 arrives on the timetable: more than half a day, so not a connection we count.