UA 3851 then AA 491 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
17:01AA 491 to Dallas-Fort Worth leaves the gatealso QR 2259, QF 3120, BA 6540
23 h 20 apart on the timetable, overnight
AA 491 leaves 23 h 20 after UA 3851 arrives on the timetable: more than half a day, so not a connection we count.