UA 3487 then K4 538 at O'Hare
Columbus (Ohio) → Chicago → Seoul
Timetable, Chicago time
09:45UA 3487 from Columbus (Ohio) at the gate
01:45K4 538 to Seoul leaves the gate
16 h apart on the timetable, overnight
K4 538 leaves 16 h after UA 3487 arrives on the timetable: more than half a day, so not a connection we count.