DL 8939 then KL 7451 at San Francisco
Phoenix → San Francisco → New York JFK
Timetable, San Francisco time
14:57DL 8939 from Phoenix at the gate
20:50KL 7451 to New York JFK leaves the gate
5 h 53 apart on the timetable
The last days
DL 8939 and KL 7451 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.