OS 254 then FR 1645 at Vienna
Hamburg → Vienna → Rome
Timetable, Vienna time
16:40OS 254 from Hamburg at the gate
06:10FR 1645 to Rome leaves the gate
13 h 30 apart on the timetable, overnight
FR 1645 leaves 13 h 30 after OS 254 arrives on the timetable: more than half a day, so not a connection we count.