UA 356 then FX 9791 at O'Hare
Phoenix → Chicago → Anchorage
Timetable, Chicago time
12:39UA 356 from Phoenix at the gate
04:00FX 9791 to Anchorage leaves the gate
15 h 21 apart on the timetable, overnight
FX 9791 leaves 15 h 21 after UA 356 arrives on the timetable: more than half a day, so not a connection we count.