A Supersonic Renaissance for Civil Aviation?
“Concorde 2.0” but greener, quieter and cheaper.
Civil aviation has yet to experience any significant increase in flight speeds since the 1960s. Two key reasons for this? Predominantly to improve fuel efficiency, but in terms of noise constraints when travelling supersonic, i.e., exceeding the speed of sound.
What if a plane could travel 40–50% faster than conventional aircraft without breaking the bank (not to mention your eardrums) and operate on net-zero carbon emissions?
Well, there’s one (actually, a few) in the works, and it’s one of the most exciting developments in civil aviation for a while.
Enter Boom Supersonic.
Before talking about their project, let’s backtrack for a second.
What happened to the Concorde?
They will build on the important legacy left behind by the Concorde between 1976 and 2003 in helping people reach certain destinations much faster than usual, with its most popular route being between London/Paris to New York. Despite the latter’s flaws, it pushed the limits, particularly with what was (somewhat) feasible with the technology at the time.
As per long-term feasibility, the faster speeds led to more energy-intensive aircraft, which, at the time when there was (rather, still is) increasing discussion about finding ways to reduce greenhouse gas (GHG) emissions, not to mention the astronomical costs involved per flight.
How much were trans-Atlantic tickets? According to Encyclopædia Britannica:
“In 1996 for example, British Airways charged $7,574 ($12,460, adjusted for 2020 inflation) for a round-trip flight from New York City to London. As a possible result, many of these flights were at half capacity, and those on board were frequently airline guests or upgraded passengers.”
Taking the price mentioned above in 1996 and accounting for inflation until 2023, this NYC to London round-trip would now cost a whopping $14,681, as per data from the US Inflation Calculator.
Regarding planes being at half-capacity, this only exacerbates the situation and would, in my opinion, have gradually led to a death spiral. In other words, the fewer flyers would be willing to fork out the moolah would need to pay extra to compensate for an under-utilised service, or the company would have been forced to offer fewer services than before, leading to less convenience, which would have also contributed to the Concorde’s demise.
Having said this, the final nail in the coffin was most likely the tragic Air France Flight 4590 on 25 July 2000, killing everyone (109 people) on board. For perspective, this was the only fatal accident in its 27-year history. Further details about this specific incident are available here.
The Concorde’s last commercial flight was on 24 October 2003. Here is a video summary of all four flights that day.
All of the information and experiences relating to the Concorde flights between 1996 and 2003 will be invaluable for Boom Supersonic, as they can build on the successful aspects of the former and produce an excellent airliner with state-of-the-art engineering and materials, much of which was either unavailable or unfeasible at the turn of the century.
Boom Overture
The Overture is Boom Supersonic’s flagship aeroplane, which uses the Symphony engine.
Some of the key benefits of this include:
— A quieter machine than comparable ones currently available. It meets Chapter 14 (the most stringent) noise standards for jet and large propeller aeroplanes.
This will allow the Overture to fly 20% quicker over land to avoid creating sonic booms in built-up areas and up to twice as fast over the ocean, reaching Mach 1.7 (roughly 1,300 miles/2,000km per hour).
“Overture’s environmental noise will blend in with the existing subsonic aircraft fleet. Overture won’t have afterburners like Concorde and its jet exhaust will be subsonic during take off.”
Joe Salamone — Boom Supersonic’s Principal Acoustic Engineer
Over time, further noise reduction and other efficiencies will allow the Overture (or any subsequent models) to fly even faster over land.
— It is designed to operate on 100% Sustainable Aviation Fuel (SAF); more on SAF shortly.
— Cheaper operating costs than comparable engines and significantly cheaper than the Concorde (when analysing everything in 2023 dollars per se). I will touch on costs throughout this and provide related articles and press releases covering the reported costs of these flights in the comments section as further details become publicly available.
Boom Supersonic and Sustainable Aviation Fuel (SAF)
Boom Supersonic aims to offer flights starting at business-class prices relative to regular passenger aeroplanes.
As per a partnership with AIR COMPANY — another US-based entity synthesising alcohols and fuels from excess CO2, mimicking photosynthesis using their patented technology — they will supply their sustainable aviation fuel to Boom Supersonic to meet the latter’s sustainability credentials.
Check out this link for a visual summary of AIRMADE’s Carbon Technology. I have also included a journal article published in September 2022 for a comprehensive scientific explanation of this process.
In a press release last September, AIR COMPANY will supply up to 5 million gallons of their “carbon-negative” fuel, AIRMADE SAF. Besides Boom Supersonic, the company will partner with JetBlue and Virgin Atlantic, supplying 25 and 100 million gallons of AIRMADE SAF, respectively.
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Alternatives to Boom Supersonic
I should acknowledge that other companies also invest in R&D for supersonic planes for civil aviation. Some other companies working on a similar product include:
Exosonic
This rival project offers a very impressive supersonic plane on paper: A 70-seater, Mach 1.8, 2x speed airliner that boats a further range than Boom: 5,000 nautical miles (5,753 miles or 9,260 km).
Exosonic aircraft are designed with sonic boom shaping technology to mute the sonic boom and avoid the disruptive booms of the past. By the time the sonic boom reaches the ground, the sonic boom will be softer, no louder than a car door closing down the street.
Their vehicles are designed to run on eco-friendly fuel extracted from CO2. To achieve this, they have partnered with California-based start-up, Twelve to convert CO2 and water into aviation fuel, plastics and many other materials derived from fossil fuels; Twelve offers a good summary of their company, objectives, products and processes in this short video.
Destinus
This Swiss-based startup is working towards an ultra-fast jet, which would blow their supersonic competitors out of the water (rather, sky) if they managed to successfully produce a hydrogen-powered hypersonic vehicle, which would translate for something exceeding Mach 5 (>3,800 miles/hour or 6,174 km/hour).
Imagine flying at that velocity, going around the world in hours instead of days.
To bring us all back down to Earth, in reality, this will most likely take the longest to approve for commercial flights in terms of passing strict safety standards and allaying any public concerns about flying at incredible speeds.
“It’s a mix of an airplane and a rocket. We call our vehicles near-space vehicles/hyperplanes.”
Davide Bonetti, Chief Engineer — Mission Design
Moreover, I expect the costs for a one-way flight in a hypersonic plane to be sky-high, just the altitude required to fly faster than normal. Despite this, we know that many individuals will be willing to fork out any amount of money just for the thrill of it, and I don’t blame them, especially if they can afford it.
Still, I give credit where it is due; hats off to these companies and many others pushing the boundaries and dedicating enormous amounts of time and effort to producing lightning-fast aeroplanes with eco-friendly fuels whilst maintaining very high standards at all times, the holy grail of aviation, in my honest opinion.
Lockheed Martin’s X-59 Quesst (“Quiet SuperSonic Technology”)
This is being carried out in collaboration with NASA’s Quesst endeavour to build a quieter supersonic aircraft. Data from these tests could open up opportunities for commercial supersonic flights over land, which are currently restricted by American and European laws in their respective regions.
Thus, other companies listed above will be closely observing how this program pans out.
According to LM’s official website, Quesst will:
— cruise at 55,000 feet (16.674 km)
— be able to reach speeds of Mach 1.4 = 925* MPH/ KPH
— produce 75 perceived levels of decibels (PLdB), akin to the sound of a car door closing, as opposed to excruciatingly loud sonic booms (105 PLdB) produced by the Concorde. This might not seem like much, but remember that these measures follow the logarithmic scale.
*Other sources provide figures between 1037 and 1065 MPH, mostly the latter, which is well above LM’s reported 925 MPH.
Playing devil’s advocate
All of the enthusiasm and hype surrounding the resurrection of passenger planes flying at Concordesque* speeds is justified, considering that so many services are at our disposal to get things done in a heartbeat.
So there’s an expectation that with major technological advancements since the last Concorde flight over 20 years ago, we can come up with aircraft that can do an even better job with cheaper operating costs and greener fuels.
Before touching on the major engineering hurdles to overcome, there are fundamental differences that some overlook when it comes to flying.
Flying in 2023 impacts productivity far less than it did in 2003.
Back then, no smartphones, no Wi-Fi (let alone fast broadband Internet), no noise-cancelling headphones, etc.
That’s just for business purposes. We have an increasing number of in-flight entertainment options for leisure travel with films, games, music, and so on.
All of these luxuries, coupled with a growth in the premium-economy class in recent years, begs the question, is paying a lot more for a supersonic flight justified? Boom Supersonic aims for their entry-level tickets to be similar to business class on a conventional plane.
Moreover, there is competition for airlines that offer ultra-long-haul flights (mind you, a 16-hour flight minimum is a f&$king slog, and not for the faint-hearted) that can provide passengers with competitively-priced flights whilst shaving a few hours off two separate trips that would have taken roughly 24 hours (as an Aussie, I know from experience).
Real Engineering’s YouTube video about the probability of Boom Supersonic pulling off the highly ambitious feat to be economically viable will provide you with an excellent analysis of the technical aspects of various supersonic aircraft, both previous and current.
Mentour Now produced a more recent piece covering their thoughts about Boom Supersonic’s ambitions, which I recommend checking out.
* Not an actual word. I’m just making up terms…on the fly.
Additional thoughts
We should always keep on an eye on potential competition that could come along and develop a superior product, which is always possible, considering the accelerating rate of technological advancements.
I look forward to even more competing projects making plenty of headway and producing a robust, reliable, economical and eco-friendly alternative that can rival The Overture, even though we are still several years away from commercial flights on one of these.
Why the need for competition? Like every industry, the competition will push companies to continue improving their products, whether range, passenger costs, a decreasing ecological footprint, etc.
The beauty of this R&D going into innovative supersonic passenger airliners is that progress relating to SAF, quieter engines and developing lighter yet robust materials into these planes will most likely help research into conventional (subsonic) counterparts, at least to a certain extent.
I admit that whilst I have a scientific background, I am no engineer and far less knowledgeable than professionals and many aviation enthusiasts; I look forward to you playing devil’s advocate and addressing any potential shortcomings from my opinions/analysis.
The biggest area to watch here will be the development of SAF to help rapidly decarbonise the aviation industry. Even though it currently accounts for roughly 2.5% of total global emissions, we need to prepare for growing levels of affluence worldwide and population growth worldwide; thus, more people in the skies = increased GHG emissions.
As a passing note, battery technology will also play a role in subsonic aviation down the track, but this will be limited to short-distance flights for the foreseeable future. Nonetheless, advancements in solid-state batteries could complement SAFs in future, though time will tell.
In countries with surplus renewable energy, this opens up opportunities for energy-intensive industries (e.g., aluminium smelting in Iceland) and could eventually play a role in the growth of green hydrogen — using renewable energy to split water molecules into pure oxygen and hydrogen gases (a.k.a., water electrolysis).
Other than nations with well-established and reliable power grids predominantly sourced from clean energy (renewables or even nuclear power) that could affordably obtain hydrogen gas (and at scale) via water electrolysis, this also creates opportunities for developing countries with abundant amounts of solar or wind energy, as per this global map shown in a related report from the International Energy Agency (IEA).
In conclusion, despite any reticence about the long-term economic viability of these next-generation supersonic and hypersonic aircraft models, there will be demand for people willing to pay extra money to fly faster than the speed of sound.
Why do I believe this? Between reaching your holiday destination faster for convenience or in an emergency, (ultra) high-net-worth individuals wanting to take advantage of this novelty per se, or the savvy businessperson wanting to maximise every second of their time, the demand will be there.
Moreover, general population growth, a growing middle-to-upper class worldwide since 2003 (when we bade farewell to the Concorde), and the push for eco-friendly fuels would further entice an ever-increasing number of affluent people to try a supersonic flight.
Even if few flights were to operate in the early days, the demand would still be there, particularly if airlines could offer supersonic flights starting at business class prices.
I am curious to see when Destinus or a similar start-up can produce aerial vehicles (powered by green hydrogen) that can transport passengers at hypersonic speeds. That will be one of the exciting aspects of ultra-fast plane travel.
Furthermore, the enormous time savings offered by Destinus’ prototype (whenever this is approved in future) will entice a cohort of ultra-high net-worth individuals to invest in or trial these vehicles.
Perhaps my analysis is pie in the sky, though I believe it holds water; time will tell.
Disclaimers
- I have no affiliation with any entity listed here and have no vested interest in Boom, Exosonic, Destinus or otherwise.
- The opinions expressed in this piece are my own and might not reflect those of any company or entity mentioned throughout this.
- The information provided here is current at the time of writing.
