The last of 1,574 Boeing 747s has left the company’s Everett, Washington plant, and will be delivered to Atlas Air early next year. That airframe wraps up a remarkable 54-year production program, with the 747 joining the Airbus A380 as the end of four-engine wide-body airliner programs. 50 years ago, “Jumbo Jets” were seen as the solution to lower seat mile costs, enabling an entirely new industry: low-cost air travel. However, the relentless drive for lower seat mile costs, combined with high fuel prices, coincided with a change in the airline industry from hub and spoke operations to point-to-point travel using smaller airplanes. 747s will remain in service as a cargo aircraft for some years, but its days as a passenger carrier are numbered.
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Episode Transcript:
It had to end eventually. With 1,574 airframes built, the last Boeing 747, a Dash-8 freighter for Atlas Air, has rolled off the assembly line at Boeing’s Everett, Washington plant. The aircraft will be delivered to the cargo carrier in early 2023. The airplane wraps up an incredible 54-year-long engineering program.
The 747 was a high-risk venture for Boeing, led by Malcolm Stamper and legendary chief engineer Joe Sutter. As an airliner, the project was spurred by Pan Am, the airline that pioneered jet transport, who wanted a plane two and a half times the size of the then current 707, with 30 percent lower seat mile costs. With advancing jet engine development, the project was feasible with 1960s technology, and Pratt & Whitney developed the JT-9D high bypass ratio turbofan for the application.
The launch customer, Pan Am wanted the aircraft by the end of 1969, meaning Boeing’s engineering teams had one-third less time than normal to design and build the most technically challenging civilian aircraft project ever attempted up to that time.
They succeeded brilliantly, although industry experts 50 years ago felt that the 747 was stopgap equipment as a passenger transport, until the new generation of supersonic transports such as Concorde and Boeing’s own proposed 2707 were developed. The distinctive hump housing the cockpit was a clever design idea to allow a nose loading door, making the 747 useful as a cargo aircraft after its anticipated passenger service ended. And that is exactly what happened, although some four decades later than expected. As the supersonic transport programs failed, the lower seat mile costs of the 747 created an entirely new industry of affordable air travel.
But that desire for lower seat mile costs, especially after the 1970s oil crises, meant aircraft either had to get bigger, or more fuel-efficient, or both. The Airbus A380 took the Jumbo concept to the next level, but after 254 airframes built, the last A380 was delivered to Emirates last year. Unlike the 747, the A380 project was not profitable for the airframe maker. Why have the jumbos disappeared? A new generation of more efficient high bypass ratio turbofans, such as the Pratt & Whitney PW4000, meant aircraft like the Boeing 777, especially when configured for high-density seating as used by Air France, can carry 747 passenger numbers, over 400 passengers, with twin engine economy. And with large twins receiving approval for long overwater operation, the economics of four engines no longer make sense for most routes.
Does this mean that four engine airliners are a thing of the past? With the airline industry moving away from the hub and spoke model and towards point-to-point service between large and medium-sized markets, the emphasis in passenger carrying aircraft today is smaller, narrow-body twins with transcontinental range.
The Airbus A321LR can carry 200 passengers over 4,000 nautical miles. And with a healthy freighter conversion program for older, large twins like early 777 variants, expect to see Boeings queen of the skies, the 747, hauling freight only in the near future.