F9 2550 then AA 5418 at DFW
Denver → Dallas-Fort Worth → Harlingen
Timetable, Dallas-Fort Worth time
09:40F9 2550 from Denver at the gate
21:48AA 5418 to Harlingen leaves the gate
12 h 08 apart on the timetable
AA 5418 leaves 12 h 08 after F9 2550 arrives on the timetable: more than half a day, so not a connection we count.