 The DC-4 returned to San Francisco as Flight 2; the Constellation left Calcutta 1330 Tuesday, stopped at Karachi, Istanbul, London, Shannon, Gander, and arrived LaGuardia Thursday at 1455.A few months later PA 3 took over the Manila route while PA 1 shifted to Tokyo and Shanghai.All Pan Am round-the-world flights included at least one change of plane until Boeing 707s took over in 1960.