Airplanes / Never Built

Boeing 2707

The Boeing 2707 was Boeing’s answer to the Concorde. It could carry more passengers, fly further, and at a speed that left the rival European creation in its wake.

But Boeing’s version of a supersonic aircraft would never make it to the market and leave behind a legacy of failure.

Today, we will answer what the Boeing 2707 was, what would it have been like inside, and why it was never built.

A bit of history … 

America always considered itself at the forefront of aviation technology. While it had been beaten to the market for the world’s first jet-powered commercial transport, its Boeing 707 had cemented its place as the gold standard of aviation travel.

But the times were changing. New military technology had opened the possibility of faster than sound commercial aircraft, turning all-day flights into mere hours, allowing passengers to eat a meal in one hemisphere, before catching the same sunset in another. Countries around the world, excited by this possibility, got to work on their own supersonic designs.

In 1962, when it became clear that the European Concorde would go ahead, with the dreaded soviets right behind, the American government gave a signal for local builders to start work on what would become the home-grown version of the supersonic transport.

Then-President John F. Kennedy tasked the Federal Aviation Administration with preparing a report on “national aviation goals for the period between now and 1970”. This report highlighted that supersonic transports, or SSTs, would be a market American couldn’t afford to miss.


In fact, many believed that the future lay in Supersonic transport, and aircraft designs like the Boeing 747 would only be a passing fad.

The race was on.

The design …

Designing an American version of the Concorde would require several different mission factors.

Boeing 747

The aircraft would need to fly between Western Europe and the Eastern USA without stopping to refuel, a range of at least 3,500 nautical miles (6,400 km)

It would also need to bring traveling fast to the masses and have a seating capacity of at least 150 passengers – meaning this bad boy would be significantly bigger than the European counterparts.

But unlike their European counterparts, America had a trick up its sleeve. The Concorde design was built around a lightweight, traditional aluminum-alloy airframe. While this had been great for heavier than air commercial airliners, it didn’t lend itself to speed and many of the engineers at the time believed that Mach 1.8 was the fastest an SST could ever go.

America on the other hand had experience with other materials like titanium. A titanium airframe had been used on the famous A-12 Blackbird, with an estimated top speed of Mach 3.35 at 85,000′ feet – significantly faster than the final Concorde design of Mach 2.04.

Thus, this American Concorde design would need to be built from a titanium structure and for lack of a better phrase, leave the rival Concorde back in the dust.


The US government would launch a contest among three different SST projects – One from Boeing, Lockheed and North American Aviation – yes the same guys who designed the rescue mission to the moon, in that very early video of mine, you can see here!

The North American Aviation NAC-60 design didn’t make it to the final selection round after being deemed too small and too slow to beat the Concorde.

Lockheed’s version would be called the L-2000 and seat over 273 passengers in the biggest and loudest SST project to date.

The Boeing effort would be called the Boeing Model 733-197, but the public nickname of Boeing 2707, as in the 2nd 707, would stick. Catchy! It would have a variable geometry wing, which gave the airframe the ability to take off and land at lower speeds and in less distance than a comparable fixed-wing aircraft. Boeing would go on to update its design twice, essentially making it bigger every time till it could seat 277 passengers in two classes (30 first-class and 247 in economy). This version would be called the 2707-100.

In 1966, the two remaining designs, 2707 and L-2000 went head to head, with the Boeing 2707 ultimately winning the contract in 1967. Lockheed’s L-2000 was judged simpler to produce and less risky for investors, but its performance was slightly lower and its noise level was slightly higher.

With the approval and a fat purse. Boeing got to work. Its design for the aircraft would go through several iterations, with a -200 model having canards at the front of the plane. Boeing would work hard on implementing its variable geometry wing, swing-wing; however, the titanium joint to swing the wings out proved much too heavy and was abandoned in favor of the traditional delta-V design. The new version would be called the Boeing 2707-300 and seat only 234 passengers and would cost the program 2-years in delays, which you’ll see is important later.


Airlines jumped on the chance to have a Boeing SST, with orders by October 1969, for 122 Boeing SSTs by 26 airlines, including Alitalia, Canadian Pacific Airlines, Delta Air Lines, Iberia, KLM, Northwest Airlines, and World Airways. The future was here.

What would have the aircraft been like onboard?

It was one of the earliest wide-body aircraft designs to have two aisles, with 2-3-2 row-seating arrangement at its widest section, with the seats getting smaller as the body tapered off. In the 2707 mock-up that Boeing built to win the control, it had both overhead storage for smaller items with restraining nets, as well as large drop-in bins between sections of the aircraft in the bulkhead – like on a long-distance train.

In the main economy cabin, there were retractable televisions placed between every sixth row in the overhead storage. In the first-class area, every pair of seats included smaller televisions in a console between the seats – something no one airline had at the time. The cabin had tiny windows, only 6 inches wide due to the high altitudes the aircraft flew at maximizing the pressure on them, but the internal pane was 12″ to give an illusion of size. Plus, the windows used rotating polarization to dim instead of shadows – an idea that wouldn’t come back until the Boeing 787, decades later

Boeing was confident, they would start construction of the prototypes in early 1967 and the first flight could be made in early 1970 – with the first airline flying a Boeing supersonic transport by 1974. By 1980, the company estimated there would be a market for a larger Model 390-475 SST, with between 700 and 1,000 aircraft being required.


So … why was this incredible machine never built?

There were three factors that caused the Boeing 2707, and the American Concorde project as a whole, to fail.

The first was the sonic boom. Several environmental groups entered the stage opposing sonic boom across the North American landmass, claiming that each flight could create a “‘bang-zone’ 50 miles wide by 2,000 miles long”. This would smash windows, scare animals, cause headaches and even perhaps ,miscarriages. Whilst overblown, the fact is that sonic booms do cause ground issues and would be a significant factor to overcome.

Secondly, environmental groups also claimed that 500 SSTs flying daily would deplete the ozone and cause increased humidity in the atmosphere. While the research didn’t really prove water vapor questions, there was a recorded drop in ozone that made some groups worried.

Lastly, and likely the most important, it came down to money. Boeing claimed that the incredible cost of the program would pay itself with orders from airlines, but noting how slow the rollout of the Concorde was, and the lack of market demand, plus the government winding back the Apollo moon missions and Vietnam war – there wasn’t any appetite for big spending projects.

The cancellation of the program in 1971 had far-reaching consequences. Boeing had to downsize its workforce by 60,000 employees, and it was followed by a downturn in the airline market. The subsequent rise in fuel prices a few years later led to airlines losing money and likely, never would have been able to pay to buy or run the Boeing 2707.

Now I just want to take a bit before the end of the video to imagine a world in which this program had gone ahead. Sure, the US government would have made a loss, but it would have changed aviation forever. If the powers that be had designed to go ahead with the 2707, and perhaps even authorize the L-2000 and NAC-60 as well, we would have seen an incredibly vibrant market of supersonic jets crossing out the world – and it’s something said that the L-2000 could have been made for cheaper and faster than the 2707, getting it in customers’ hands faster. This would have led the Boeing 747 would become a cargo plane, or not built at all, and the A380 would never have existed.

Is this a world you want to live in? Let me know in the comments down below. If you enjoyed this video, then I highly suggest that you check out the rest of my work on the channel.

Interestingly, you can take a quiz on this topic and find out how many questions you can answer correctly. It’s right here. Good luck!

See you next time.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Quiz: Boeing 747X

May 29, 2021

Quiz: Boeing 2707

June 1, 2021