Engine makers sound downbeat on supersonic, leaving Boom in a bind
flightglobal.com
flightglobal.com
Constraints on the customer base:
- Absolutely must have face-to-face meetings on another continent
- Rich/"important" enough to pay for business-class transcontinental flights
- Can't do any productive work on a normal flight, so important to reduce flight time
- Not staying for a long visit, so cutting a couple of hours from the flight is important (Edit: added this item)
- Not rich enough to fly charter
That's a tough set of criteria, especially with CFOs looking to cut unnecessary business travel. Zoom is a lot cheaper than business-class travel.
Seriously, we know for a fact that all internet communications have been completely compromised for a long time. If they have ever been safe. It makes plenty of sense if money is no object and certain things have to be discussed. That said, it's a massive waste. I wonder what happened to Musk's idea to have rockets fill that niche
Metadata though... that's another story.
If you're doing a longer road tour anyway, saving a few hours on the transatlantic legs doesn't really buy you a whole lot.
Supersonic flight over the continents is problematic, but not everyone lives on a coast. So many customers will have to take slow planes to aggregation hubs, which can easily add hours to an itinerary. Edit: And the aggregation hubs may not all serve the same destinations. Could easily see SF residents having to fly commercial to NYC to catch a Boom to London, even though there might be a Boom that flies SF-Tokyo.
Once you add up the fixed time costs of getting to the airport, security, flying to a supersonic hub, the percentage of time that can potentially be shaved off the itinerary dwindles.
I flew business multiple times, Frankfurt-SF (~14h), and it's a breeze if you can lie down and sleep. Not even boring. Jet lag is way worse than the flight itself.
The longest scheduled flight right now is probably SIN to JFK at 18h30m. Qantas wants to do a 20h JFK-SYD route.
And, yes, a private supersonic would be even faster but then it becomes even more of a question about the size of the market.
After months of mostly living in a hotel, she got tired of it, told he boss she wanted to go back to basketball training in her home town so wanted a different project.
Her boss solved it by flying her to Prague and back every week so she could make basketball training on Thursday nights.
I think that if there was supersonic flight they’d happily have found her a project in New York next and foot the bill, twice a week, just so she could keep going to basketball training and still run the project in person.
Btw, that sounds like the worst solution your sister could have agreed to. She was tired of living in a hotel but is willing to keep living in an hotel and also fly back and forth between Prague and Amsterdam every week?
And even if she was a good representative, look at the ratio: 10-20 engineers to 1 project manager flying supersonic. I'm not sure that's a great market niche.
> if there was supersonic flight they’d happily have found her a project in New York next and foot the bill, twice a week
I do have to laugh at this, because there are numerous consultants who do this now, using our current planes.
Edit: Amsterdam<->NYC 4x monthly for business/first class (equivalent to Boom pricing) looks like it will shake out in the range of $30k monthly in airline tickets. Very few employees in a company will justify that kind of travel spend. (And still not fly on a corporate jet.)
The most miserable part isn't even the flight itself - it's the hassle at the airports.
It was unavoidable for some people twenty years ago. Now it is a badge of stupid.
And we wonder why the planet is set to "broil."
"Who cares, someone else is paying for it."
Also keep in mind that supersonic won't help beyond the coasts due to noise/overflight rules that would require flights to slow down over the continents anyway.
If there was a supersonic LAX-Singapore (I doubt India would allow supersonic planes), at least the longest leg of the trip is mostly over ocean, supersonic, and the Singapore-DEL flight is just a normal one.
The JFK-Singapore direct would still be hundreds of km longer.
And even for personal flights - considering that I have to travel only once a year between India and the US, I would very much welcome this option.
The current 24 hour long journey is just too brutal, and often time constraints mean that I can't break the journey into small hops over 3-4 days. And I shudder taking my family with me on such trips, given how much of a stress it causes.
So $1,100 for today vs $7,000 for supersonic (using business class fares as a proxy) to save 9 hours of flight time. My assertion is that there's relatively few people on any given route who have enough money and fly that route enough to make this a viable niche outside of a very limited set of routes.
> I shudder taking my family with me on such trips
I hear you on that! But also the notion of spending $7k for each of us is somehow worse.
Using the example above, that would put supersonic flights in the range of 10x economy, which feels about right for airline pricing. (At least until there are tons of supersonic flights to push down prices.)
If they actually can get 4,250nm of usable range, you might be able to do something in Japan to SEA or maybe SFO, and that routing would make more sense probably.
But this is really really unlikely to ever fly - the physics and economics are so stacked against this until something really tectonic happens with how we store and use energy... but like not fossil fuels. It would need to be something that borders on "free", like if fusion existed, and was safe, easy and light.
And I'm not sure that Air France was actually making money. The story I heard was that AF wanted to retire their fleet after the accident, because they hadn't made money on it. BA balked because they were making money but having to pay full costs of fleet maintenance equipment, rather than splitting those with AF, changed the numbers enough that BA would have lost money, so the whole fleet was retired.
Business class from east to west (via emirates and qatar for example) can sometimes (more often pre-covid) be grabbed for $1000 above an economy ticket. The departing US business class ticket costs often seem very specific to our market. A lot of people on HN can bump up their tickets while flying outside the country even just for vacations.
The growing backlash against the environmental impact of private jets may change this calculation a bit.
That kind of diffuse luxe stuff will not get cleaned up by pushback.
Startups, especially if any hardware is involved, mostly need to be companies that are leveraging an entire stack of off-the-shelf, on-the-market, mostly commodity components into a product or solution which is mostly, at least at first, a packaging exercise on the HW side and perhaps novel go to market (AAS, for example), UI/UX, etc. experience on the SW and solution side. Very few startups are going to work outside of these guide rails, and even when they do the exit/invested is pretty poor at this point and has been getting poorer for at least 20 years. You get to tweak the last 5-10% of your tech stack in HW and had better have something really compelling as a result.
There's probably _business_ in SST but between the tech stack, the dependencies, and just plain practical business issues like liability/etc. not a business that you get to as a startup.
Boom is just the same. The chance it will fail is about 90%. But if it does succeed, it will return much, much more than 10x to their early investors.
Boom has a 99.999% chance of failing. Without an engine lined up, they aren't even in the business they're claiming they are, and haven't been for years.
As for Boom, I have to admit, they have a problem.
The problem is that companies like GE that make jet engines, can make quite some nice profits by selling to the military. The XA100 [1] most likely exceeds any requirements Boom can only dream of, but being military technology, it is off limits for them. If GE lands a fat contract to provide engines for the F35, then they'll sell thousands of engines, with very little uncertainty. Getting involved with Boom will only complicate their life. If they don't fully compartmentalize the two departments, they can get in trouble. If they do, there's no synergy. Plus, the doubts will always be there that they leak military technology to the civilian side.
That's a shame. GE makes some incredible jet engines.
Maybe the war in Ukraine will end and one day Putin won't be president anymore, and Russia won't be under sanctions. Then Boom could buy an engine from Saturn, such as [2], the engine that powers various Sukhois. The military-civilian tension will still be there, but Russia will need to export things, so maybe a deal could be made.
The math for efficiency and maintenance is just different for sovereign governments, maybe a derivative could be made more efficient with less maintenance required.
Fighter jets require like 6 hours of maintenance for every hour of flight - sure, it's not just the engines, but it's a big part of it.
The real problem boom has is the number of viable flights is _very_ low - really just the ones Concorde flew (NY-LON, NY-PAR), and Concorde never made money.
A couple comments up someone claimed DXB-NYC being a route - more than half of the great circle route is over land, and it's more than 50% longer than the rosy projections Boom put out. Realistically, they'll be lucky if they're within 10% of their stated range. But of course, not without an engine.
This is what 4,250nm would get you from JFK: http://www.gcmap.com/mapui?R=4250nm%40JFK
We also didn't care about being green back during the Concorde - but Supersonic flights will likely be 5x-10x worse on a per passenger seat mile basis for emissions. Really hard to get around wind resistance being a square of velocity.
That's a common misunderstanding. Very common.
In cruise mode Concorde was as efficient as a Boeing 747.
When you go faster, you do two things: 1. reduce the angle of attack, 2. fly higher. Concorde was flying twice as high as subsonic jets. The end result is that you still get increased drag, but much less than the square (or cube) of velocity would suggest.
Ok, but increased drag it is, right? Right, but you go faster. If your drag goes up by a factor of 2, but your speed by a factor of 4, then in the end you burn less fuel. It so happens that Concorde's drag went up virtually by the same factor as its speed.
The problem with Concorde was that it was horrible aerodynamics during the takeoff stage. At that point the plane is the heaviest (its has full fuel tanks), so the problem was compounded by some sort of "tyranny of the rocket equation".
Can Boom solve this problem? My guess is that this was their pitch to investors. In the 50+ years since Concorde was designed, both computers and computational fluid dynamics experienced huge advances. The computer I'm writing this on has probably performed more flops since I started writing this comment than the entire computational modeling for Concorde in its decade-long work.
As for military engines (and their maintenance) being expensive. F-35 is like a Formula 1 car, as USAF general Charles Brown once said. Its engines are pushed to the limit on a constant basis. A commercial jet is very different. It does not need to pull huge Gs. Its trajectory is very, very predictable. I'm sure a company like GE could make a very cost efficient jet engine for Boom. It's just that they have much better ROI if they build engines for F-35.
Yes - a plane that carries 550 passengers vs a plane carrying 100.
Also, the game has changed a fair bit - no one is building 4 engined planes anymore - because while it was about as efficient as a 747, it’s going to be less than half as efficient as a 777. That carries 400 passengers.
The wiki page I linked quotes an L/D ratio for Concorde (in cruise mode) of 7 to 7.5 and for Boeing 747 of 15.3 to 17.7. Taking the mid-points of 7.25 and 16.5 we get that the L/D ratio for Boeing is 2.275 higher than of Concorde. But Concorde's speed was 2.41 times higher than Boeing's (Mach 2.05 vs 0.85).
There are 2 things to go from here to actual fuel per passenger*mile. How much fuel do you need to produce the same thrust, and how much aircraft do you need to carry a passenger. On both counts, supersonic airplanes have a problem: supersonic engines have a lower bypass ratio, so they are inherently less efficient, and supersonic planes need to be sturdier, and therefore heavier than subsonic ones.
These problems are hard.
But the difficulty of building a supersonic aircraft does not come from the air resistance being the square of the speed.
By the way, the L/D ratio decreases with the speed, but it does not tend to zero in the limit. This fact is actually stunning, if you think of it. As the speed goes up, at some point the L/D ratio stops decreasing, so you end up burning significantly less fuel per mile. That's the reason some militarizes invest in hypersonic missiles: they have much longer range than their size alone would make you think.
These problems are hard.
Lift induced drag goes down as velocity decreases, parasitic drag goes up as velocity increases. There’s there’s wave drag to contend with. Yes there’s weird places where going faster is helpful, but I doubt we’re going to see real net efficiency gains going faster than Mach .8-9 anytime soon.
So, can Boom compete with subsonic airplanes. Where can they have an edge?
They have two actually:
1. they are a startup. Boeing and Airbus are old and ossified. Smaller manufacturers are probably not as ossified, but they already have a niche, so their risk appetite is different: they prefer to put their research money to work towards incrementally improving their current designs. Boom is in a life and death situation, they have a huge fire under their feet, and so they'll get more research done for the same amount of dollars
2. Clean slate. All current civilian airplanes are cylinders with flat wings. It's a proven formula. Manufacturers don't want to move too much from a proven formula. But Boom does not have this type of fetters. In particular, they can design a body that follow the Whitcomb area rule [1]. Which is what they are actually doing [2]:
Contoured fuselage: According to the principle of area-ruling, Overture’s fuselage has a larger diameter toward the front of the aircraft and a smaller diameter toward the rear. Boom has applied this design technique to minimize drag and maximize fuel efficiency at supersonic speeds.
Will the manufacturing costs explode? I guess they should be higher than for traditional geometries. But that works to their advantage: it keeps the current manufacturers from trying these non-standard geometries, and keeps them in a local optimum from which they find it harder to move. But it won't be a dealbreaker for a premium aircraft. That's basically the Tesla Roadster gameplan.
[1] https://en.wikipedia.org/wiki/Area_rule
[2] https://boomsupersonic.com/news/post/boom-supersonic-reveals...
But even if you assume there's a viable transatlantic market for supersonic flight, you probably can't charge all that huge a premium over business/first. If your premium has to be 2x to 3x, I doubt you have a market.
Handwaving away noise issues with supersonic flight over land gets you closer to something viable. But you still need economics that aren't that different from an all business-class subsonic. (And my understanding is that British Airways had trouble making all business work on the London to New York route.
I don't know - the all-business class A318 service from London City to JFK ran from 2009 to 2020 and was up to two flights a day for a significant part of that time. I guess it was really Covid that killed it.
https://en.wikipedia.org/wiki/SABRE_(rocket_engine)
Mind you, I've been hearing about that since I was at high school and I'm in my late 50s. :-)
And composite materials like on the A350 and 787 have been around, see the A350 and 787.
The plane doesn't exist either, it was a plan.
> And composite materials like on the A350 and 787 have been around, see the A350 and 787
Their point of comparison is the Concorde. If they can make a plane that is significantly cheaper than the Concorde, thanks to the great tech that is now mainstream (composites, turbofans, CAD) but wasn't back then, it can be similar in cost to modern day business class, while still being supersonic. At least that was their marketing pitch, i don't see it taking off without an engine.
The faster you go in an atmosphere the more the atmosphere resists. It gets less and less efficient the faster you go. That's just how it works.
Of course it would be less efficient than a subsonic jet, but they never claimed the opposite - the idea was for it to be faster, but not (much) more expensive than today's business class on subsonic jets.
This is actually not even approximately true; like many aerodynamic phenomena, drag is super nonlinear in airspeed and not even monotonic, with a bunch of weird outcomes around mach 1. The first chapter of every aero textbook probably includes a variation of this famous chart [0], showing drag coefficient or sometimes drag force (estimated for some famous/classic airframe) as a function of mach number.
This is why prolonged supercruise can exist for airplanes without giant comical fuel tanks etc.
That said, your main point about CAD/physics definitely stands and is a good one; imho it would be unlikely to design and build e.g. a 10x better airplane than the Concorde today, even with all the fancy computers simulations etc.
[0] https://www.researchgate.net/figure/Drag-coefficient-as-a-fu...
Computers are great for marginal gains and saving labor costs, but they can't give a 10x improvement unless there's already a 9x improvement in materials and techniques. Small nit, but CAE is simulations, while CAD is just drafting.
Even if your drag coeficcient goes down from 0.3 to 0.25, doubling your velocity will still more than triple your fuel consumption over constant distance. Then the tradeoffs in airframe to make it not fall out of the sky in the transonic regime, then the loss of ISP from much lower bypass engines, then the smaller cabins, then carrying the extra fuel... you can carry far fewer passengers. Sure your drag went down substantially from mk 0.98, but noone is proposing doing a transonic trip because that would be insane.
You wind up using many times more energy per passenger, meaning you pretty much only have first class due to noone on a budget even considering paying 10x as much. Throw in the cost of SAF and you're looking at the price of a house per ticket in order to save 5 hours in the air from a total 15 hours travel/boarding/waiting time.
You are making two assumptions, one explicit and one implicit. That the cross-section area is constant (it’s not, it depends on the angle of attack, which is smaller at higher speeds) and that the air density is constant (it’s not, supersonic planes fly at much higher altitudes, where the air is thinner).
You're making a similarly dishonest equivocation by carefully trying to frame the problem as if it were a mystery and the problem hadn't been reduced to lift/drag ratios 70 years ago. Which have an easily calculable upper bound for supersonic flight, by the way.
A supersonic craft has a much worse lift to drag ratio than a subsonic one. A supersonic craft even has a worse lift to drag ratio than the same supersonic craft at subsonic speed.
You can't even optimize your craft for that high altitude high speed regime because it still has to fly at lower speed and altitude and make it through the sound barrier without getting destroyed.
You will be using at least three times the fuel, so will need at least three times the ticket price. But that's not the only place a basic understanding of kinetic energy disqualifies the entire concept. Your engines/fans will also need at least double the effective exhaust velocity so their energy needs per unit of thrust will be doubled.
With this we can predict that all other things being equal, a supersonic craft will use about 6-10x the fuel per passenger mile as a subsonic one. A 747 has a bit over double the range and 4-6 times the passenger count as a concorde, so the naive approach got us in the ballpark.
Then for long haul flights (the only kind where supersonic will save time) existing airliners are almost half fuel by mass, which means you're in the regime of the rocket equation rather than having fuel scale linearly with distance. Then you can't offset business and first class with economy tickets and freight because noone is going to fly economy supersonic for 6-10x the cost or pay 6-10x the shipping for no perceptible time saving. With the previous in mind though, the supersonic craft is going to be limited to about 4 hours in the air before you start to lose passenger capacity to fuel. So it's not even great for long haul.
In short. Unless fuel prices drop dramatically ticket prices for a new supersonic craft would be commensurable with a new apartment for time savings of around 4 hours or at best 30% of the total door to door time.
The Concorde engine was efficient at cruise - and pretty awful everywhere else. At cruise it was about 10% more efficient than a GE90. But the Concorde had 4 of them, and a 777 has 2 GE90s.
This is also why you don't see 4 engined planes anymore, except for the A380 and most people were hell bent on retiring during the pandemic until they couldn't get more 787s/A350s and the 777X is delayed.
The other stuff is incremental efficiencies, not enough to fundamentally change the very challenging math of supersonic flight efficiency.
It doesn't much matter what is/isn't possible, or what could/couldn't be economical, if the company & engineers who say they are working to develop it...are not actually capable of shipping even a puny nerfed toy version of their supposed product.
My guess: the RR engineers concluded "maybe it's possible, but these idiots will never achieve it". Then quietly shared that with their colleagues at other engine makers.
Haven't seen any explanation on why Boom can't just buy a few current fast jet engines for their demonstrator.
My impression is that Boom was not looking to RR for engines for their demonstrator, but for their full-size production model. Those engines would have to be carefully designed & optimized for economic long-haul supersonic operation. (Vs. existing supersonic military jet engines are basically cost-no-object gas-guzzling hot rods.)
Three GE J85-15 engines for the XB-1 demonstrator.
The "small supersonic aircraft" which is what the XB-1 is, is a solved problem. "Advanced composites" is irrelevant, any aerospace firm can make a supersonic-capable aircraft out of "advanced composites". Scaled Composites build SpaceShipOne in three years with about a hundred people in a hangar.
But Boom hasn't gotten the XB-1 into the air after five years and tons more cash.
Building a new supersonic airframe: easy
Building a new supersonic jet engine: hard
Literally and actually with no exceptions every single modest-sized aerospace firm can build a supersonic airframe. That problem is solved. Tens, if not hundreds, of thousands of supersonic aircraft have been built and many of them are capable of carrying passengers.
This is not an exaggeration. My employer isn't even in the supersonic aircraft business and we could build and fly a supersonic aircraft if some executive got a wild hair up his butt, in less time and money than Boom. Tiny and embargoed firms in a variety of foreign countries with small or non-existent aerospace industrial bases have done it.
The research into the aerodynamics and stresses on supersonic airframes is done.
Engines are hard. There are only a handful of companies with the expertise and cash needed to develop a supersonic jet engine, especially one that can super cruise.
Boom is saying "yah we're gonna build a supersonic passenger jet, uhhh, don't worry about the engine we'll figure that out later, give cash please".
What Boom is doing is functionally equivalent to an EV startup saying "Yeah we're going to design a car that can go 300mph (easy, individuals {Bob Dauernheim, for one} in garages have done it) that is powered by electric motors (hard) that don't exist yet and that someone else will design" and then getting hundreds of millions of dollars to design the chassis while negotiating with motor and battery suppliers to do the R&D into the hard bit at their own risk with the promise of profits from future sales to all of the people who want a 300mph EV.
Especially if the plane needs long runways to takeoff.
Due to the travel times others have touched on to the major airports in nearly all big cities.
Lighter private jets have a huge advantage in travel time of being able to take off from the closest small airports.
If it's a really long route, like Sydney to London, then it would start making sense. But this could not support the thousands of engines needed to break even on R&D costs.
* Airport-to-city travel time
* Airport security time
* Optimize boarding (very straightforward solutions but require passenger education)
* Speeding up taxiing / takeoff sequencing (not sure how but there's gotta be a better way than what we do now)
Each of those are challenging but would be more impactful (and more solvable?) than supersonic flight time!
When something like Boom announces:
American said it too had paid a “non-refundable deposit” – it also did not say how much – as part of an agreement to buy up to 20 of the jets.
Ick.
If it was more like 3x, that might make it work on a cost benefit in certain cases, but physics makes fools of us all it seems…
Much easier and faster experience. That's how JSX operates.
They don't have an engine for a plane that they have yet to fly, for a concept that has limited commercial viability in the first place. We will look at companies like United and American Airlines that signed letters of intent to purchase these as foolish idiots.
In the day and age of remote meetings, there is nearly no alpha in being able to be in London three hours earlier from NYC. You would simply hop on a Zoom call if it were that urgent. Nobody is going to pay up for the cost if they are flying for leisure. There are limited viable routes in in the first place.
Has it cost them anything at this point? A little PR bump for zero expense and zero consequences doesn't seem all that foolish.
Unlike Theranos, supersonic engines already exist and they are regularly used by the military. The issue is that none of the big boys are willing to pony up a lot of money to build, test and certify one for civilian use unless they can definitely get paid for their effort.
And yes, there are willing buyers who will pay ludicrous amounts for comfort or speed, as the increasingly elaborate arms race in first class (eg. multi-room suites a la Etihad's Residence) and the entire private jet market demonstrate. The Concorde was profitable towards the end of its life despite mind-bogglingly high fuel costs, so there's definitely a market if -- and it's a big if -- Boom can pull it off.
It’s a very bold statement to say when you have no evidence that Boom would or even could ship an airplane that would put people’s lives in danger.
Theranos was not simply a company that made large promises that required leaps in technology and then lied repeatedly about having succeeded in making those leaps. They risked patient safety by providing phony blood test results. It’s important not throw around that epithet unless it’s earned.
To really be Theranos-tier, they'd have lied about having the engine already. They didn't go that far, they never claimed to have the engine already. Nor is the engine they desire one that's actually impossible, as Therano's vision was.
You also wouldn't need to add any additional infrastructure as opposed to ideas like vac-trains or MAGLEV in general.
You still need one of the most expensive parts of that infrastructure which is the rights of way, stations/highway interchanges and a transport corridor from the city to an airport (which can't be as close as a conventional airport due to 5x the flight volume, louder engines and sonic booms).
The 900km of a rail corridor in the low population regions doesn't cost as much as that 30km of highway or metro tunnel directly under the CBD and 70km of arterials, onramps and interchanges.
I foresee the failure of all supersonic airplane ventures until NASA comes up with a viable sonic-boom free design. Even then, the fuel burn could still make it unsalable.
Does anybody know more about this "military variant"?
That would not fit inside of Boom's aircraft.
Developing a jet engine that could allow Boom to meet its performance targets is a nation-state level endeavor.
In reality a Starship flight would probably sell few very expensive seats instead; just like Boom's aircraft only has 50 seats. Which would make it worse than subsonic flights in terms of fuel used, but still competitive with supersonic.
For a flight time between 20 (minimum) and 40 minutes (maximum) to anywhere on earth, this volume could comfortably fit 1000 passengers per flight.
At 2 or 3 times the price of a regular ticket, their offer would be a direct competitor against business class tickets, if they can reduce enough the risk, and handle logistics of rapid reuse.
Also, starship has more pressurized volume than a 747. You can fit a lot of people.
This means you can spend more fuel/be less efficient overall for a much more comfortable acceleration profile.
In terms of safety, starship will fly hundreds, perhaps thousands of times before people fly on them. They'll get there.
Realistically, P2P using giant rockets is a nothing but a pipe dream. Just straight forward things like weather proof this. The latest F9 launch had to be scrubbed two times due to unfavourable weather at the launch site, for example.
Now multiply that just that weather-risk by two, since the landing site also requires good conditions at the same time.
Then there's the "little things" like airspace closures, launch permissions, boarding procedures, the requirement for personal pressure suits (simple masks won't do in case of cabin pressure loss), etc.
The idea sounds so easy on paper, but there's a lot of good reasons that in over 60 years of crewed space flight, the idea hasn't even been demonstrated.
Now for the launch platform, it will have to be built about 30km from shore, and could be accessed by high speed train, the travel time would be 15-20 minutes from the shore
Fuck dang, time to cycle residential proxies.
That said, see sibling comments about fineness. In addition to being fine in the shiny variety, starship is a portly fellow. It will be able to land in anything less than a hurricane.
Boom can increase fuel efficiency via the airplane architecture with e.g. composites. The near commercialisation new civil aircraft from china achieved a 10% reduction doing so. The same can be said for noise reduction. Hence what Boom should do is simply to order Rolls royce to produce the same engines again. However one should know that R&D for the successor of the concorde engine has already been spent and such engine has been designed. Unfortunately the U.S imperialist oppressive bans killed the concorde economics before the production of said engine, cf: https://en.wikipedia.org/wiki/Rolls-Royce/Snecma_Olympus_593....
Now about the noise levels let's adress the fact that it is a non-issue. 1) If you look at the empirical scientific comparisons, the mean noise of the concorde is significantly lower than many civil airplanes, especially the ones with 4 engines. 2) The boom while intense, is very transient. It is not heard from people inside the airplane. It is a non-problem for the obvious reason that your jet does not need to be supersonic for 100% of the trajectory, therefore a plane can and should go to very high altitude (already a supersonic requirement) and/or above low density population (rural, ocean) and only then bypass the speed of sound, making the noise boom a moot problem. While this solution is trivial, political bans and people hysteria isn't.
What is at stakes? A lot of things, supersonics isn't just cool, it is a life saving technology that can allow the transfer of key people in records time (expert surgeon in niche disease emergency for example) which can have very high utilitaristic value. It can also make it much more pratical for key people to meet physically (e.g. key academicians for a symposium about advancing the state of the art in a topic) which is high impact considering cognitive biases regarding human agency.
Note however there are other supersonic engine makers than rolls royce, for example any country that makes supersonic military jets can obtain such engines. It is easy to forget that the first commercial supersonic engine was not the concorde but a russian tupolev. While the tupolev has reliability issue, few know they had an alternative engine (likely more reliable). In addition to the tupolev engines, I would look into the state of the art https://en.wikipedia.org/wiki/Saturn_AL-31 Regarding SOTA civilian turbofan there is the https://en.wikipedia.org/wiki/Aviadvigatel_PD-14#PD-35 in development, although it can power an antonov (!) and seems very versatile I wonder if (not a turbojet) it can perform supersonicity without afterburners.
regarding those options however, russia bad, china bad.
https://en.wikipedia.org/wiki/General_Electric_XA100 https://www.geaviation.com/press-release/military-engines/ge...