AA 1998 then 5Y 7143 at O'Hare
Los Angeles → Chicago → Tokyo Narita
Timetable, Chicago time
20:00AA 1998 from Los Angeles at the gate
02:155Y 7143 to Tokyo Narita leaves the gate
6 h 15 apart on the timetable, overnight
The last days
AA 1998 and 5Y 7143 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.