Supersonic passenger aircraf​t – why did they fail?

Radek Zatloukal

The aviation industry is a highly competitive market, in which manufacturers race against each other and push themselves to the limits when it comes to innovation. Huge companies like Airbus and Boeing invest millions and millions of dollars to produce lighter, more fuel-efficient, more comfortable and, of course, faster airplanes than their rivals. And yet, the speed of the most commonly used commercial airplanes has not changed much in the last 50 years. We most certainly do have the technology to overcome the regular cruising speed of 900km/h the passenger planes usually fly.  So why do we not have commercial supersonic flights?

            To understand why today’s aircraft are relatively slow, we have to look into the past. The 1960s saw not only a race between the USA and the Soviet Union to reach space and the Moon, but also a race to have the first supersonic commercial aircraft. The USA held a design contest for a supersonic aircraft, which was eventually won by Boeing, who beat four other American aviation companies. However, the design of the Boeing 2707 proved to be too ambitious and the US government eventually decided to end the funding, thus killing the project before it could be finished. One of the factors contributing to the failure was unconfirmed concern for the environment (it was presumed by some scientists that such aircraft could destroy the ozone layer) and the so-called sonic boom. Objects flying faster than the speed of sound generate loud shockwaves that can be heard dozens of kilometres away. In an experiment to test the tolerance of the US population to the sonic boom, the US government approved Operation Bongo II, which involved military jets flying over the densely populated city of Oklahoma, creating numerous sonic booms. After receiving hundreds of formal complaints from the angered citizens and several property damage claims (such as cracked windows), the experiment was ended early.

The Soviet Union’s Tupolev Tu-144 was meant to provide proof of the Union’s technical superiority and success. And on paper, it did. The Boeing 2707 never even saw the light of day, while Europe’s Concorde was slower and could carry fewer passengers. Its top speed of 2430km/h was unheard of. Furthermore, the Tu-144 was introduced two months sooner than Concorde. However, even though the Tu-144 was largely based on stolen blueprints of Concorde, it had major flaws in its design, especially when it came to passenger experience. For instance, the engines were so loud that the passengers could not talk to each other and instead had to communicate by passing around hand-written notes. What is worse, the project was riddled with technical failures and malfunctions. One of the biggest setbacks for the Tu-144 was the crash at the 1973 Paris Air Show, which killed all six crew members and eight people on the ground. The Tupolev also had a very limited range and could not even make a transatlantic flight. Given the fact that supersonic aircraft are most useful when travelling long distances, this feature of the aircraft appeared very impractical, and it severely limited the use of the Tu-144. In fact, it was only used on a single route, between Moscow and Almaty, the capital of Kazakhstan. All in all, the Tu-144 project was a huge disaster, despite the government’s efforts to conceal its flawed design, it was a source of great embarrassment to the Soviet Union. 

The British-French Concorde entered service in 1969. Notwithstanding a few technical hiccups, it was considered a victory for both countries in the competition for a supersonic passenger aircraft. It was much more comfortable to fly with than the Tu-144, because the engineers built the airplane with a thought for those for whom it was intended. Only the richest of the rich could afford the astronomical price of the ticket (a London to New York return flight cost approximately 12,000 dollars, compared to 1500 dollars for the economy class in a regular jet), so it was crucial the flight was luxurious and comfortable. Despite being an icon of technological success in the West, it was a commercial failure. An underwhelming total of twenty Concordes was built, and due to the sonic boom, they could only reach the speed of sound when over unpopulated areas. The Concorde was retired in 2003. Currently, there is not a single supersonic aircraft in use.

Concorde was a wonder of modern technology, but it failed business-wise. The problem is, passengers care about price before speed. The fact that Concorde cut the flight time from London to New York in half was not enough when you consider that you could travel luxuriously in business class for 50% of the Concorde fare. Not to mention the fact that even though Concorde was posh and comfortable, due to its slim design it had to compromise when it came to leg room. You could easily recline your seat and sleep comfortably in business class for half the price, instead of saving a few hours cramped in your seat on Concorde.

Not all hope for supersonic travel is yet lost, however. The are several projects in the making that explore the idea of travel above the speed of sound once again. Maybe this time the engineers and CEOs will learn from the mistakes of the Boeing 2707, the Tu-144 and Concorde and aviation will finally make a huge leap forward, leaving the speed limit of 900km/h behind.