In '93 and '94 I took UA 914 IAD>GVA and return by UA 915 several times. This flight actually was a 747 or 767 for the IAD>CDG leg and a 727 for the CDG>GVA leg. I think that CDG was used as a local hub and that several 727 were stationed there. Pan Am also used to service GVA, first via ZRH and later via CDG.