DL 1909 then 9K 6178 at JFK
Salt Lake City → New York → Boston
Timetable, New York time
05:00DL 1909 from Salt Lake City at the gate
12:559K 6178 to Boston leaves the gate
7 h 55 apart on the timetable
The last days
DL 1909 and 9K 6178 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.