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Important milestone -

In early 2025, the American Company Boom Supersonic achieved an important milestone when its XB-1 supersonic demonstrator aircraft went airborne.

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Long time coming -

This was the first time that a piloted non-military aircraft flew faster than the speed of sound since Concorde made its last flight in 2003.

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Ambitious plans -

The flight of XB-1 was an important step in Boom Supersonic’s ambitious journey towards making supersonic airliners ready to carry passengers by 2029.

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Prevailing concerns -

Not all stakeholders are convinced, however, that the project will succeed, or even that the Boom Supersonic’s vision has much merit.

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What is supersonic travel? -

Let's start by taking a look at the definition of supersonic travel. In a nutshell, it refers to an aircraft that moves faster than the speed of sound.

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The Mach number -

When experts talk about supersonic flight, they often refer to the 'Mach number' of the aircraft. This is defined as the plane's speed divided by the speed at which sound waves move through the air.

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Breaking the sound barrier -

Aircraft that break the sound barrier, i.e. fly faster than the speed of sound, have Mach numbers greater than 1.

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Disturbing the air -

In order to understand the significance of the Mach number, you must first consider that as a plane flies, it disturbs the air in front of it.

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Forming shockwaves -

These disturbances move at the speed of sound, and in the case of supersonic flight, they combine to form shock waves around the aircraft.

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Trapping the sound -

The shock waves around the aircraft trap the sound that it makes, and until those shock waves move to your position on the ground, you will not hear the aircraft.

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Main benefit -

The main benefit of supersonic travel is that it is much faster than subsonic travel. Indeed, the companies working on supersonic jets claim that they can drastically reduce journey times.

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Plans at Boom Supersonic -

Boom, for example, plans to build an aircraft called Overture that will fly at Mach 1.7. For perspective, current passenger jets usually cruise at around Mach 0.8.

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Big plans -

The company claims that with Overture, a trip from New York to Rome would take just four hours and 40 minutes, rather than the eight hours it currently takes.

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Plans at Spike Aerospace -

Another company getting involved in the action is American firm Spike Aerospace. The team at Spike Aerospace is developing a supersonic business jet.

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Tagline -

The tagline for the ambitious project is "delivering the world in half the time." This phrase neatly encapsulates the value proposition of supersonic passenger aircraft.

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The history of supersonic air travel -

Of course, this is not the first time that airlines have built supersonic passenger jets. In fact, they were already around in the 20th century.

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Remembering Concorde -

The most famous supersonic airliner of days gone by was Concorde, a Franco-British aircraft operated by British Airways and Air France between 1976 and 2003.

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Concorde statistics -

Concorde cruised at Mach 2 and had a maximum capacity of 128 (usually rich and famous) passengers. It regularly flew from London to New York in three hours.

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The failure of Concorde -

For several years, many people thought that Concorde was the future of commercial air travel. However, it failed for a number of reasons.

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Fuel inefficient -

Firstly, although it was designed to cruise efficiently at supersonic speeds, the Concorde was extremely fuel-inefficient when taking off and landing.

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Gas guzzling -

Very quickly the airliner earned a reputation for being a "gas guzzler," and this was the main complaint leveled against the technology as the years went on.

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US government ban -

Another reason Concorde failed was that in the 1970s, the US government placed a ban on supersonic passenger flight over land.

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The problem with sonic booms -

The government chose to enact the ban due to the risk of sonic booms—the loud disturbances that occur when the shock waves from a supersonic jet propagate to the ground.

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Major challenge -

In extreme cases, sonic booms can shatter windows and damage buildings. How to handle them properly is a major challenge of supersonic passenger travel.

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Going forward -

If companies in the 21st century want to have more success with supersonic airliners than Concorde, they will first need to solve the issue of the sonic boom.

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Managing sonic boom -

The aim of the NASA and Lockheed Martin Quesst project is to show that the sonic boom can be dissipated to manageable levels.

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Dissipation -

Quesst has proposed that, by using the geometry of its X-59 aircraft (which has an elongated nose), it will be able to dissipate sonic booms to a weak "thump."

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Collecting feedback -

As part of the project, the X-59 aircraft will fly over US cities and citizens will be given the opportunity to provide their feedback.

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Solving the fuel problem -

In terms of the fuel efficiency problem, in the 21st century, it should be possible to fuel supersonic jets with sustainable aviation fuel.

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Sustainable aviation fuel -

For Overture, for example, Boom Supersonic plans to use 100% sustainable aviation fuel, in order to reduce the greenhouse gas emissions and the carbon footprint of the aircraft.

Sources: (CNN)

See also: The best places to travel to in 2025

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