AA 6251 then K4 556 at O'Hare
Milwaukee → Chicago → Tokyo Narita
Timetable, Chicago time
21:00AA 6251 from Milwaukee at the gate
09:05K4 556 to Tokyo Narita leaves the gate
12 h 05 apart on the timetable, overnight
K4 556 leaves 12 h 05 after AA 6251 arrives on the timetable: more than half a day, so not a connection we count.