DL 4050 then DL 1909 at Salt Lake City
Tucson → Salt Lake City → New York JFK
Timetable, Salt Lake City time
14:20DL 4050 from Tucson at the gate
23:36DL 1909 to New York JFK leaves the gate
9 h 16 apart on the timetable
The last days
DL 4050 and DL 1909 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.