WN 2851 then DL 9935 at Phoenix
Denver → Phoenix → San Diego
Timetable, Phoenix time
11:05WN 2851 from Denver at the gate
12:00DL 9935 to San Diego leaves the gate
55 min apart on the timetable
The last days
WN 2851 and DL 9935 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.