 IAS Cargo Airlines acquired additional, second-hand Britannia turboprop freighters as well as a Canadair CL-44 "swing tail" freighter during the early 1970s to expand its fleet in response to growing worldwide demand for its pure freight services.When the world's major scheduled airlines began re-equipping their fleets with new generation widebodied jet aircraft from the early 1970s, a growing number of older generation, narrow-bodied jet planes, such as the Boeing 707 and the Douglas DC-8, became available on the second-hand market at prices smaller airlines that were lacking the resources to invest in new equipment could afford.IAS Cargo Airlines became one of these smaller airlines that took advantage of this situation by purchasing its first DC-8-50F jet freighter in 1974.