AA 3903 then UA 3923 at Phoenix
Yuma → Phoenix → Denver
Timetable, Phoenix time
21:14AA 3903 from Yuma at the gate
22:10UA 3923 to Denver leaves the gate
56 min apart on the timetable
The last days
AA 3903 and UA 3923 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.