NH 8421 then JL 751 at Narita
Chicago → Tokyo → Hanoi
Timetable, Tokyo time
18:38NH 8421 from Chicago at the gate
18:00JL 751 to Hanoi leaves the gate
23 h 22 apart on the timetable, overnight
JL 751 leaves 23 h 22 after NH 8421 arrives on the timetable: more than half a day, so not a connection we count.