When Airbus started in 1970, road vehicles were initially used for the movement of components and sections; however, growth in production volume soon necessitated a switch to air transport. From 1972 onwards, a fleet of four highly modified "Super Guppies" took over. These were former Boeing Stratocruisers from the 1940s that had been converted with custom fuselages and the adoption of turbine engines to carry large volume loads for NASA's space program in the 1960s. Airbus' use of the Super Guppies led to the jest that "every Airbus is delivered on the wings of a Boeing".[2][3] As time went on, the Super Guppies grew increasingly unsatisfactory for Airbus's ferrying needs: their age meant that operating expenses were high and ever-increasing, and growing Airbus production required greater capacity.