UA 1780 then KL 7451 at San Francisco
Dallas-Fort Worth → San Francisco → New York JFK
Timetable, San Francisco time
17:17UA 1780 from Dallas-Fort Worth at the gatealso AC 3148, VA 8579, NZ 9092
21:35KL 7451 to New York JFK leaves the gate
4 h 18 apart on the timetable
The last days
UA 1780 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.