They enabled airlines to carry far more people at greater speeds, while providing unprecedented comfort for passengers and unprecedented profits for airlines.
Aircraft manufacturers introduced a new generation of large, four-engine airliners after World War II that soon dominated U.S. and international air travel and helped lower fares. These new airliners were built with profitable transcontinental air routes in mind. They enabled airlines to carry far more people at greater speeds, while providing unprecedented comfort for passengers and unprecedented profits for airlines. As a result, competition increased and fares fell, thus opening up air travel to even more people.