UA 3851 then AA 1401 at San Francisco
Rio De Janeiro → San Francisco → Dallas-Fort Worth
Timetable, San Francisco time
17:41UA 3851 from Rio De Janeiro at the gate
15:45AA 1401 to Dallas-Fort Worth leaves the gatealso QF 4572
22 h 04 apart on the timetable, overnight
AA 1401 leaves 22 h 04 after UA 3851 arrives on the timetable: more than half a day, so not a connection we count.