A new Concorde-style supersonic passenger jet could slash flight times to Australia in half within the next decade.
The X-59 Quiet Supersonic Technology aircraft is being built by Lockheed Martin – assisted by NASA – to perfect quiet sonic booms that would allow the plane to go supersonic over land.
Concord, which was last flown in 2003, could not fly over land due to a powerful sonic boom that broke the sound barrier.
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The X-59 Quiet Supersonic Technology aircraft is being built by Lockheed Martin – assisted by NASA – to perfect quiet sonic booms that would allow the plane to go supersonic over land
Concord, which was last flown in 2003, could not fly over land due to a powerful sonic boom that broke the sound barrier. Pictured: The X-59 concept
The X-59 is designed to cruise at 55,000ft at about 940mph and create just 75 Perceived Level decibel (PLdB) – about as loud as a car door closing.
Lockheed Martin said the move ‘marks a milestone to bring supersonic commercial travel over land one step closer to reality.’
It comes after Qantas embarked on a 19-hour non-stop flight from London to Sydney earlier this month, with the new X-59 expected to half that as it reaches speeds of up to Mach 1.45.
What is NASA’s ‘Son of Concorde’ X-plane?
Nasa is developing a 1,100mph (1,770kph) aircraft that has been dubbed the ‘son of Concorde’.
The vehicle is the first in a series of aircraft Nasa is developing with Lockheed Martin in a quest to build a commercially viable supersonic jet.
It is designed to fly at Mach 1.4 (1,100mph / 1,700 kph) at an altitude of 55,000 feet (10 miles).
Dubbed the X-59 Quiet Supersonic Transport (QueSST), the research craft aims to cut out the sonic booms associated with supersonic travel.
The aircraft is shaped to separate the shocks and expansions associated with supersonic flight to reduce the volume of the shaped signature, and was developed by Lockheed’s Skunk Works over 20 years.
The team is hoping to achieve a sonic boom 60 dBA lower than other supersonic aircraft, such as Concorde.
Recent research has shown it is possible for a supersonic airplane to be shaped in such a way that the shock waves it forms when flying faster than the speed of sound can generate a sound at ground level so quiet it will hardly will be noticed by the public, if at all.
A spot in one of the plane’s 40 seats is also understood to be cheaper than Concorde, which were £5,774 – now worth about £10,000.
But Lockheed Martin, which normally produces military aircraft, is facing stiff opposition.
Denver’s Boom Super-sonic has received 76 orders from groups including Richard Branson’s Virgin and Japan Airlines.
It is also believed to be faster, reaching Mach 2.2 and topping Concorde’s Mach 2.04.
Boom wants to cut times from London to New York to three hours, 15 minutes, but will only be able to fly at speed over the sea.
Peter Peter Iosifidis, Low Boom Flight Demonstrator program manager at Lockheed Martin Skunk Works, told the Sunday Express: ‘Though a technological marvel, Concorde was a business failure. Commercial success wasn’t the first priority, and that’s why not many were built.’
He added: ‘Other producers are not addressing the noise issue. Flying a supersonic jet only over water is restrictive, the only benefit being the faster speeds.
‘If you’re only flying fast from London to New York can you sell enough tickets to enough passengers to make it successful? And with our technology just around the corner, their shelf life is limited too.’
The X-59 will conduct its first flight in 2021.
It will be used to collect community response data on the acceptability of the quiet sonic boom generated by the aircraft, helping NASA establish an acceptable commercial supersonic noise standard to overturn current regulations banning supersonic travel over land.
Last November NASA began tests to see how Texas residents reacted to noise from experimental aircraft.
The space agency launched a research project as they continued to experiment for its next airliner dubbed the ‘Son of Concorde’.
Two F/A-18’s used in the trials climbed to at 55,000 feet/ 17 km above the gulf of Mexico last year and began a dive towards Texas accelerating trough the sound barrier about 23 miles from the coast before pulling up and back out to sea
NASa and Lockheed Martin have already completed wind tunnel and simulation tests of the radical design (pictured)
The aim of the testing was to see if residents living near the Texas Gulf Coast heard noise from the jets, travelling faster than the speed of sound, without making the explosive noise of a sonic boom.
The company claimed the noise it would make doing 940mph or 1,515 kmph would be ‘no louder than the clunk of a car door closing’.
Jerry Baker, 46, who lived behind the island’s sea wall, was one of the 500 residents recruited by NASA to listen out for noise and heard ‘several loud bangs’ during the experiment.
‘The first one was the loudest,’ he said last year. ‘It rattled the windows.’
But he said the next day the thumps were quieter. ‘I just heard one, right at eleven o’clock.’ ‘Very small, two tiny bumps.’
The X-59 is designed to cruise at 55,000ft at about 940mph and create just 75 Perceived Level decibel (PLdB) – about as loud as a car door closing
NASA hoped the result of the sonic tests will convince aviation authorities to change regulations on flights over land to allow for a new generation of supersonic jets.
Concorde operated from 1976 until it petered out in 2003 because of the cost of running he aircraft, the crash of 2000, the threat of terrorism after the September 11 attacks and the noise of loud sonic booms in residential areas.
What was Concorde?
Concorde was a turbojet-powered supersonic passenger jet that was operated until 2003.
It had a maximum speed over twice the speed of sound at Mach 2.04 (1,354mph or 2,180k per hour at cruise altitude) and could seat 92 to 128 passengers.
It was first flown in 1969, but needed further tests to establish it as viable as a commercial aircraft.
Concorde entered service in 1976 and continued flying for the next 27 years.
It is one of only two supersonic transports to have been operated commercially.
The other is the Soviet-built Tupolev Tu-144, which ran for a much shorter period of time before it was grounded and retired due to safety and budget issues.
Concorde was jointly developed and manufactured by Aérospatiale and the British Aircraft Corporation (BAC) under an Anglo-French treaty. Concorde’s name, meaning harmony or union, reflects the cooperation on the project between the United Kingdom and France.
In the UK, any or all of the type are known simply as ‘Concorde’, without an article.
Twenty aircraft were built including six prototypes and development aircraft.
Air France (AF) and British Airways (BA) each received seven aircraft. The research and development failed to make a profit and the two airlines bought the aircraft at a huge discount.
Concorde was retired in 2003 due to a general downturn in the commercial aviation industry after the type’s only crash in 2000, the September 11 attacks in 2001, and a decision by Airbus, the successor to Aérospatiale and BAC, to discontinue maintenance support.
The first flight of the X-59, which could one day fly from London to New York in just three hours without giving off a loud sonic boom, is scheduled for 2021.
The craft could become the first commercial supersonic aircraft to carry passengers since the iconic Anglo-French jet Concorde was decommissioned 15 years ago.
Ahead of this, the space agency will use a modified combat jet to check the ‘acoustic signature’ of the engines to be used in the airliner, by sending it into a series of dives.
It recruited 500 people on the ground to answer surveys about the noise generated by the the F/A-18 Hornet, to ensure the flight was quiet as it flies over Texas.
Before the aircraft takes to the skies, NASA was investigating whether members of the public are put off by the noise produced by X-59 when it breaks the sound barrier.
Tests used an F-18 fighter jet to conduct dive manoeuvres off the shores of Galveston, Texas – an island city near Houston.
The plane rapidly descended from almost 50,000 feet (15,200 metres), briefly going supersonic and firing off the sound likely to come from X-59 aircraft.
The noise, which NASA called a ‘sonic thump’, should sound more like a car door slamming as opposed to the booms produced by existing supersonic aircraft.
The agency measured the sounds using sensors on the ground while gathering public reaction through a series of surveys.
Originally named the Low-Flight Flight Demonstrator by Nasa, the agency announced in June last year the aircraft was to be called X-59 QueSST.
The US Air Force made the name change in-part as a hat tip American X-plane history, which began in 1947 with the world’s first supersonic plane, the Bell X-1.
The X-59 project aims to cut out the noisy sonic booms that echoed above cities in the era of Concorde, while travelling at speeds of 1,100mph (Mach 1.4 / 1,700 km/h).
The loud booms that rang out whenever a Concorde broke the sound barrier were often described as ‘unsettling’ by members of the public, which ultimately limited the aircraft to flights over the Atlantic when it began carrying passengers in 1976.
X-59 is designed to stop shockwaves triggered by the movement of air particles when an aircraft breaks the sound barrier from merging – a phenomenon that gives off the telltale sonic boom of supersonic aircraft.
NASA is developing the aircraft with Lockheed Martin’s aeronautics branch with test flights planned for 2022. The plane is dubbed the Quiet Supersonic Transport (QueSST) low-boom flight demonstrator (artist’s impression)
How will NASA reduce the sound of sonic booms?
In a conventional supersonic aircraft, shockwaves from the nose, cockpit, inlets, wings and other features come together as they move through the atmosphere into strong shocks emanating from the nose and tail.
These are known as bow and tail shocks, respectively.
As these shockwaves pass over the ground, air pressure rises sharply, declines, then rises rapidly again.
It’s this that produces the classic ‘double-bang’ sonic boom.
Reshaping the aircraft to produce a longer, more slender shape is the best way to generate shockwaves of lower, more equal strength that do not form into such strong bow and tail shocks.
Nasa and other organisations are working on creating shapes to reduce sonic booms.
Stretching the nose to break the bow shock into a series of weaker shockwaves is particularly effective.
This lowers and spreads that initial pressure peak and softens the first bang of the sonic boom.
NASA’s tests last year produced similar shockwaves using an F-18 fighter jet to conduct sharp manoeuvres in the air.
The aircraft, piloted by Nasa researcher Jim Less, dived from 49,000 feet (15,000m) and go briefly supersonic before levelling off at 30,000 feet (9,000m).
Shockwaves produced by the manoeuvre will concentrate directly below the aircraft in the form of a very loud, focused pair of sonic booms.
A few miles from the dive points, the noise quickly trails off as they spread out and weaken.
QueSST is the latest addition to the X-series of experimental aircraft and rockets, used to test and evaluate new technologies and aerodynamic concepts.
Their X designation indicates their research mission status within the US system of aircraft naming.
This all dates back to Chuck Yeager’s sound-barrier-breaking craft, the X-1, a rocket engine–powered aircraft, designed and built in 1945, that achieved a speed of nearly 1,000 miles per hour (1,600 kmh) in 1948.
Nasa’s vision for the X-59 was approved by the US budget, released by the Office Of Management And Budget In Washington DC in February last year.
The space agency was awarded $19.9 billion (£14.3bn) for the next year, $500million (£360m) more than the previous year.
It is not known what proportion of this was been allocated for the supersonic aircraft project.
QueSST will be used as a test bed for technologies that could make their way into commercial planes.
NASA is hoping to see the first flight tests take place in 2021 or 2022, with public reaction tests to the final aircraft scheduled for 2022 or 2023.