DE 5253 then QF 3654 at San Francisco
Las Vegas → San Francisco → New York JFK
Timetable, San Francisco time
22:27DE 5253 from Las Vegas at the gatealso CX 7851
23:00QF 3654 to New York JFK leaves the gate
33 min apart on the timetable
The last days
DE 5253 and QF 3654 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.