DL 3901 then WN 3980 at Salt Lake City
Helena → Salt Lake City → Phoenix Sky Harbor
Timetable, Salt Lake City time
08:38DL 3901 from Helena at the gate
20:50WN 3980 to Phoenix Sky Harbor leaves the gate
12 h 12 apart on the timetable
WN 3980 leaves 12 h 12 after DL 3901 arrives on the timetable: more than half a day, so not a connection we count.