Operational history thumb|Atlas Air Boeing 747-400 at Adelaide Airport, operated as a cargo airline After the aircraft's introduction with Pan Am in 1970, other airlines that had bought the 747 to stay competitive began to put their own 747s into service."Ready or Not, Here Comes Jumbo." Time, January 19, 1970. Retrieved: December 19, 2007. Boeing estimated that half of the early 747 sales were to airlines desiring the aircraft's long range rather than its payload capacity.Smith, Bruce A. "Boeing Shuns Very Large Jets While Aiming for Longer Range." Aviation Week and Space Technology, January 1, 2001, pp. 28–29.747X vs A380 "How to Reduce Congestion" (PDF). Department of Aerospace and Ocean Engineering, Virginia Tech. Retrieved: December 10, 2007. While the 747 had the lowest potential operating cost per seat, this could only be achieved when the aircraft was fully loaded; costs per seat increased rapidly as occupancy declined. A moderately loaded 747, one with only 70 percent of its seats occupied, used more than 95 percent of the fuel needed by a fully occupied 747."Airline reporting on fuel consumption." Miljominsteriet (Danish Environmental Protection Agency). Retrieved: December 13, 2007. Nonetheless, many flag-carriers purchased the 747 due to its prestige "even if it made no sense economically" to operate. During the 1970s and 1980s, over 30 regularly scheduled 747s could often be seen at John F. Kennedy International Airport.
Operational history thumb|Atlas Air Boeing 747-400 at Adelaide Airport, operated as a cargo airline After the aircraft's introduction with Pan Am in 1970, other airlines that had bought the 747 to stay competitive began to put their own 747s into service."Ready or Not, Here Comes Jumbo." Time, January 19, 1970. Retrieved: December 19, 2007. Boeing estimated that half of the early 747 sales were to airlines desiring the aircraft's long range rather than its payload capacity.Smith, Bruce A. "Boeing Shuns Very Large Jets While Aiming for Longer Range." Aviation Week and Space Technology, January 1, 2001, pp. 28–29.747X vs A380 "How to Reduce Congestion" (PDF). Department of Aerospace and Ocean Engineering, Virginia Tech. Retrieved: December 10, 2007. While the 747 had the lowest potential operating cost per seat, this could only be achieved when the aircraft was fully loaded; costs per seat increased rapidly as occupancy declined. A moderately loaded 747, one with only 70 percent of its seats occupied, used more than 95 percent of the fuel needed by a fully occupied 747."Airline reporting on fuel consumption." Miljominsteriet (Danish Environmental Protection Agency). Retrieved: December 13, 2007. Nonetheless many flag-carriers purchased the 747 due to its prestige "even if it made no sense economically" to operate. During the 1970s and 1980s, over 30 regularly scheduled 747s could often be seen at John F. Kennedy International Airport.