General Electric akanga kupayona pfungwa asi akanga vakazvipira kukudziridza injini nokuda C-5 Galaxy uye haana kupinda yezvokutengeserana pamusika kusvikira gare gare. Pratt & Whitney akanga achishandawo pamusoro chete nheyo uye, pakazopera 1966, Boeing, Pan Am uye Pratt & Whitney akabvuma kukudziridza injini itsva, akasarudzwa JT9D kuti simba 747. The chirongwa chakagadzirirwa pamwe itsva nzira inonzi kukanganisa muti ongororo, izvo akabvumira migumisiro kukundikana chikamu chimwe chete kuti kudzidza kuona yayo dzimwe hurongwa.
kubvumidza kuti ishande kubva kunhandare dzendege dziripo