The airlines full name was Guest Aerovias Mexico SA. It was founded by Winston Guest in 1946 and opened in 1948 with long-haul services to Madrid. These services proved difficult for the small airline to sustain and later they abandoned the route.
Guest were more successful locally and their regular routes included Mexico City to Guatemala City, Panama, Balboa, Curacao, Caracas and Bogotá. They also offered services between Mexico City and Miami and Bermuda from the early 1960s.
Once Guest had acquired long-range aircraft (in 1959) they re-opened their Madrid route. In addition they served Lisbon and Paris. On these routes initially they used ex-S.A.S DC6s but these were later replaced by Lockheed Super Constellations.
In late 1960 it was announced that Aerovias Guest planned to replace their Super Constellations on the Mexico City-Paris route with two Comet 4Cs which they were to lease from Mexicana.
de Havilland staff were called on to train Guest crews alongside Mexicana staff. In April 1961 route proving and training flights began between Mexico City and Paris returning via Lisbon. The two 4Cs used for these flights were XA-NAR and XA-NAT. Scheduled ‘Guest’ Comet services began in the spring of 1961.
See Flight Engineers Log for more details of specific training flights. See Mexicana for dates of the Comets disposal.