WN 3045 then WN 2170 at Denver
Tucson → Denver → St Louis
Timetable, Denver time
09:55WN 3045 from Tucson at the gate
14:20WN 2170 to St Louis leaves the gate
4 h 25 apart on the timetable
The last days
WN 3045 and WN 2170 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.