JL 6740 then 7C 1164 at Narita
Hanoi → Tokyo → Busan
Timetable, Tokyo time
09:42JL 6740 from Hanoi at the gate
14:057C 1164 to Busan leaves the gate
4 h 23 apart on the timetable
The last days
JL 6740 and 7C 1164 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.