BA 711 then AA 87 at Heathrow
Zurich → London → Chicago
Timetable, London time
12:40BA 711 from Zurich at the gate
12:35AA 87 to Chicago leaves the gate
23 h 55 apart on the timetable, overnight
AA 87 leaves 23 h 55 after BA 711 arrives on the timetable: more than half a day, so not a connection we count.