Boeing's very first jetliner, the 707, began commercial flights in 1958. A scant 10 years later, the demand for air travel was so great that Boeing unveiled its new 747 to the world, which held more than twice the number of passengers as the 707. Originally, the 747 was to be a double-decker configuration, but engineers struggled with freight capacity and the ability to rapidly evacuate passengers in the event of an emergency. 

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Boeing's very first jetliner, the 707, began commercial flights in 1958. A scant 10 years later, the demand for air travel was so great that Boeing unveiled its new 747 to the world, which held more than twice the number of passengers as the 707. Originally, the 747 was to be a double-decker configuration, but engineers struggled with freight capacity and the ability to rapidly evacuate passengers in the event of an emergency. 

Read More: https://www.jalopnik.com/1912333/boeing-747-fuel-burn-per-hour-capacity/