BA 217 then YX 3287 at Dulles
London → Washington → Dayton
Timetable, Washington time
15:40BA 217 from London at the gate
12:35YX 3287 to Dayton leaves the gate
20 h 55 apart on the timetable, overnight
YX 3287 leaves 20 h 55 after BA 217 arrives on the timetable: more than half a day, so not a connection we count.