I think it is important to note that the real competitor to supersonic planes is actually WiFi on commercial aircraft. Unlike the Concorde era, you’re no longer disconnected while in the air.
WiFi maybe useful (not sure what it adds since reading, writing and watching downloaded videos on a PC or tablet works without WiFi) to some business flyers, but even if you can make more use of the time on a 12 hour flight, cutting flight time to 6 hours would be a bigger win in terms of jet lag and total time for someone flying in for a single day’s meeting.
I think the big breakthrough was lie flat seats in business class. Yeah, I know it sucks in the economy/economy plus cabin, but being able to lie down, stretch out and get some sleep makes a huge difference. Flying from YVR to SYD, for example, is 14 hours and works out nicely with dinner, a night's sleep and breakfast before morning arrival in Australia. It would be nice to do the flight in 7 hours or even less, but there's still the big time zone difference. The longer flight works pretty well with an evening departure and a morning arrival. A shorter flight would just mean conking out at a hotel on arrival rather than being ready for a fresh day.
This leaves the obvious trade off. Assuming the aircraft can be built, supersonic flights are going to be a premium item. No one will be flying trans-Pacific supersonic for $1K a seat. The competition will be for the business and first class passenger paying $5K to $30K a seat. The Concorde was fast, but did not offer what we would now consider a premium class seat. The seats were small and cramped. The food might have been good, but the cabin was overheated. (Does Boom have a plan for the cabin cooling system? You could burn your hand on the SR-72 window.) It was better than conventional first class at the time if one was willing to trade comfort for time, but premium class has improved since. Now, it's more like the old Atlantic Clipper except with a mechanical contrivance to turn one's seat into a bed.
I can see a market for supersonic private jets. They'd pander nicely to oligarch egos, and the interior design could be personalized, so comfort would be less of an issue than for a commercial service. The problem is that there are only so many customers for a $100M+ private jet, and current redistributive policies are tightening things even at the high end of the asset/income curve. Billionaires who might be customers are being squeezed by a smaller cohort of ten- and hundred-billionaires, so the market is not growing.
One other point why the SpaceX comparison is not valid: a major reason for the slack in space travel is the rockets' non-reusability. SpaceX fixed that; in fact the difference between their external prices and their internal cost is probably rather large given how many "unpaid" Starlink launches they do.
Airline travel has the opposite problem, in that base prices are much too low; large airliners requires a dose of artificial scarity and a mix of seat prices to be even moderately profitable. (Or, if you're a cheapskate airline, absurd surcharges for literally everything.)
Getting a supersonic plane to the point where it's profitable, considering its high fuel consumption and running cost, esp. per passenger, will be extremely difficult, if not impossible. Personally I'd bet on the latter.
Simple question: why would anyone name an aircraft manufacturing company "Boom."
They should have thought a bit slower than the speed of sound, and realized their attempt to be clever actually elicits imagery of aircraft -> exploding.
There’s another company called Hermeus building a hypersonic aircraft with future commercial plans. First fully functioning aircraft would be for the defense space.
I would add a fifth point to your list: Manufacture a supersonic airliner and engine in series production. Designing aircraft and engines that are manufacturable is not the same as designing a a prototype. Supersonic aircraft and engines will likely require some exotic materials. Obtaining land area, facilities, skilled work force, and a supply chain of reliable suppliers requires a ton of capital, time, and very capable management. There is also the time, skill and money required to get through flight test and certification.
Great, but not sufficiently pessimistic analysis (former P&W engineer here, from long ago). If you add "...commercially successful..." to your question, the answer is a short "no." Maybe a few private jets, if people pour enough cash onto the bonfire.
Space launches are a different economy than flying Joe and Jane from NY to Paris.
That's a bit like saying that a Nissan Micra with a good entertainment system is a competitor to a Ferrari.
The time value of supersonic travel doesn't make sense unless you earn millions per year. A decent proportion of people flew Concorde were doing it as a once in a lifetime experience. Fundamentally it's a luxury good that strokes the ego rather than a practical timesaving.
It's also a value signalling tool much in the same way driving a Lamborghini at 15 mph through the streets of London is, subconsciously people perceive that your time is worth £10 million a year if you fly Concorde, even if it isn't.
I worked at one of the companies mentioned in this post, the flying policy was basically if you were the CEOs first line you could fly private jet or business class whatever was easiest. For everyone else it was fly standard class, fly a day early and take a room in a hotel to sleep off your jet lag, get a chauffer driven car to wherever to need to go after flying but no business class. Hotels are $200 a night, chauffeured car is $100 and you cost $1000 per day, its didn't ever make economic or welfare sense to go business class never mind supersonic.
Failure cost of an airliner - immediate and reputational - has to be a lot higher than a rocket flight. Most rocket flights are considered risky. They are generally unmanned. If they do have a few humans on board, they have accepted there is a chance of death. Operating at 1 in 100 rocket flight catastrophic failure seems to be acceptable. Airlines need to be something like a million times better.
I think this is one of the few articles to get that key point that aerospace is mostly expensive because you are competing against very large incumbents who are constantly working on up-grading their product offerings.
I think the better analogy than SpaceX is Gould Racing:
Gould will sell you a single seater car that is 95% as fast as an F1 car for ~£150k, their cars mostly race in Hill Climbs. F1 cars cost hundreds of millions to develop and run and yet aren't take much faster but it's worth it to win in F1.
I think the issue for Boom isn't going to be hitting the performance targets or even making it work. I think the issue will be making it for a reasonable cost. That Gould works being you can go out and buy a lot of the parts from a mature race car supply chain. The issue for Boom will be how often they need to pay for novel components which when added up over the cost of the plane could easily make it several times their estimated cost and thus a complete economic non starter.
One aspect of supersonic flight might strongly affect the usability of its service : time difference.
When flying East-to-West on Concorde, you would arrive at an earlier time than you arrived, which meant you could conduct business on the same day you travelled. On the way back, the same speed means that you lost a nights sleep. A supersonic transpacific flight would exacerbate the issue (losing a full sleep and arriving at a not-so-convenient hour.
First/business class seats now allow you for some degree of resting, meaning that you can fly when you sleep.
The ennemy of supersonic flight is no so much ZOOM or WiFi as it is lie-flat airplane seats.
To what extent does the business case change if the regulatory requirements are relaxed? Another business strategy famously pursued by Uber is banking on deregulation as a way to lower operating costs.
Uber was never about reducing operating costs. Uber rides cost passengers about the same as taxi rides did if one adjusts for inflation. Uber drivers do about as well as taxi drivers did. (Some would argue they do worse.) The point of Uber was to take over and unify the taxi dispatch business, and it makes its money by taking a cut of just about every ride in the area.
The ride business was fragmented. There were only so many areas where one could do a street hail. If you wanted a taxi dispatched, you had to choose a dispatcher which was like choosing a good line at the supermarket. All the "sharing", efficiency, self-driving and so on were just distractions from the real business model which was establishing a monopoly.
Actually I think people conflate Uber with Lyft. Uber was focused on the black car business model while Lyft was focused on regular people driving regular cars becoming taxis. Kalanick got fired for trying to explain that to a guy that invested in black cars while business model…and ironically Lyft benefited from the fallout. Btw, I was around Twitter early adopters and the Twitter executives didn’t plan on the early adopters using it the way they did.
Driving isn't like flying a plane. Many of the externalities which when driving are a minor nuisance (like, tired driver bumps against another car, or the engine seizes up) are fatal to a bunch of people on a plane. in this case, likely to be high-net-worth people. Say goodbye to your company's profits, if not your company.
The current regulations in the US limit aircraft speeds over land instead of limiting the actual sound energy of sonic booms. The regulation should be changed, since the speed of the aircraft doesn’t cause the negative externalities, just the actual sound. Boom Aero claims to have solved this by shaping the boom sound waves so that they reflect back up away from land and say they have proven it with the XB1 flight, but if that’s true, then they are depending on that regulation to be changed, although it’s not an issue for the most lucrative routes (NY-London/Paris and LA-Tokyo/Seoul).
Range is a challenge for SSTs, because of the inevitable range-payload-speed trade off, which is made tougher (for commercial purposes) because passengers are likely to place a higher value on cutting hours off LA-Tokyo or LA-Sydney than cutting 30 minutes from NY-SFO. As you may recall, Concorde never had the range to do transpacific commercial flights, and it was a big sales problem. A secondary problem is that when one approaches the edge of the envelope, the ability to fly long distances with a commercial payload becomes sensitive to prevailing winds--as in most days yes, some days no. It would be very annoying for passengers to pay an extra $10,000 for a fast trip, only to discover the doubtful pleasures of duty-free in Kamchatka while the plane refuels.
Range was a huge issue with the Concorde. There were only a handful of runs that made any sense at all. I was always surprised they never did the west coast to Hawaii run as it was in range, but the planes were probably full of vacationers not business travelers. (There's also the lack of a landing alternative on route.)
Ah, thanks. That page does beg the question how often weather conditions are, or are not, such that a sonic boom gets reflected upwards, not to mention that Mach 1.2 is a somewhat minor speed advantage that's unlikely to justify the ticket price.
Thus they'll have to target intercontinental flights. Even so, Mach 1.7 is not going to beat the Concorde's speed record.
That would be much harder to do. I'm sure it is possible to do a technical analysis of energy levels reaching the ground, and all it would take is money for Boom to buy the analysis that it wants. I've done technical analyses, so I know that a lot of the work is figuring out the results the customer wants then adjusting the analysis to produce believable numbers in the right ball park. It's one of the reasons I left the business.
A more realistic approach would be to actually monitor the energy that reaches the ground, but this is horribly easy to game, and some parties noise complaints are taken more seriously than others.
Hmm - yeah I guess my thought was more to do with the testing and certification requirements referenced in the article. Though of course the claims about the wave shaping could actually be as a bulwark for those as well.
This might be slightly off-topic but I thought this was the best place to discuss this important issue. Is green tech growth linear or exponential? I was reading in last week’s wsj an article by j Doyne farmer who claims green tech growth is exponential. He cited that solar power is 10,000 times cheaper then when it was first used in a nasa mission in the 1970s. He also cited landlines vs. cell phones. The fact that in less then 20 years most people have gotten rid of their landlines for cell phones. But then Charles Murray the author of long hard road: the lithium-ion battery and the electric called j Doyne farmer’s type of thinking “Moore’s curse” being that Moore’s law only applies to electrics but for example washing machines it doesn’t apply. Does anyone have any thoughts regarding this?
In general, applying Moore’s law to anything other than the number of transistors on a chip is wrong. A solar cell has silicon with a simple NP junction and does not benefit from the advances in EUV lithography that are what increases the number of transistors. There are advances in production of the polysilicon used, and learning in the manufacturing processes which has brought down the cost of solar cells, but even the great cost reductions apply only to the cell. To use a cell for commercial power generation, it needs to be built into a panel with an aluminum or steel frame, glass (strong enough to survive hailstorms and snow cover), copper or aluminum wiring and connectors. Then panels need to be assembled onto an adjustable metal frame and wires together with more copper wire, and then a large inverter is needed to convert the DC voltage from the cells to higher voltage AC synchronized to the grid. The cost reductions (not from Moores law) are all in the cell itself, the glass, frames, wiring, as well as land and labor costs determine the bigger part of the cost of solar electricity, so all those graphs showing 98% reduction in the cost of a cell are just distracting planners from the actual costs involved, which will not be going to zero even if the cells were free.
We know that the envelope is a logistic curve with slow growth initially, higher growth as the economics improve and then slow growth after green energy sources have replaced most other energy sources. There are other obvious limits. There is only so much solar energy per square meter and it is highly variable. There is only so much wind or tidal energy to capture.
I think we're still in the early part of the rapid growth section of the curve. There's a lot of money in the field, and we're seeing all sorts of technical advances involving materials that could improve efficiency. For example, two layer solar panels could nearly double energy production. We're also seeing work on fuel cells and sodium batteries that could dramatically reduce the cost of power storage. If the storage problem can be solved, it could drive increased adoption of green energy.
I'm not sure how popular a 1-hour flight from JFK to LHR airport will be when there's still a 1-hour commute, 1/2 hour (at least) check-in time on the departing end and another 1-hour commute on the arrival end. Sure, in NYC, you can take a Blade helicopter to JFK in 5 minutes, but you still have to drive, or be driven to, the Blade heliport at 33 and the East River, through midtown traffic, and you might get expedited clearance through check-in on a high cost supersonic flight, but all that adds cost. The projected ticket price is estimated to be around $5,000 for a one-way flight at Mach 5 (cited in Nextbigfuture's blog, but I can't find the article from a few days ago now).
That's a lot of money to save a couple of hours flying time, when there are much faster alternatives over Zoom.
I doubt that $5K number. That's on the order of what it costs to fly business class on a conventional jet nowadays. I'm sure, at $5K one way, they'd sell lots of seats for supersonic JFK-LHR flights, but I don't see how they'd make a profit except by having enough capital to sell seats at a huge loss until they've driven out all their competitors.
I would have expected that supersonic business jets would arrive before airliners. Dassault makes Rafale fighters and their latest Falcon is supposed to reach Mach 0.925.
I think it is important to note that the real competitor to supersonic planes is actually WiFi on commercial aircraft. Unlike the Concorde era, you’re no longer disconnected while in the air.
There is also the comfort factor. Look at the seats on the Concord vs business class (or even premium economy) on a 787 or A350.
WiFi maybe useful (not sure what it adds since reading, writing and watching downloaded videos on a PC or tablet works without WiFi) to some business flyers, but even if you can make more use of the time on a 12 hour flight, cutting flight time to 6 hours would be a bigger win in terms of jet lag and total time for someone flying in for a single day’s meeting.
I think the big breakthrough was lie flat seats in business class. Yeah, I know it sucks in the economy/economy plus cabin, but being able to lie down, stretch out and get some sleep makes a huge difference. Flying from YVR to SYD, for example, is 14 hours and works out nicely with dinner, a night's sleep and breakfast before morning arrival in Australia. It would be nice to do the flight in 7 hours or even less, but there's still the big time zone difference. The longer flight works pretty well with an evening departure and a morning arrival. A shorter flight would just mean conking out at a hotel on arrival rather than being ready for a fresh day.
This leaves the obvious trade off. Assuming the aircraft can be built, supersonic flights are going to be a premium item. No one will be flying trans-Pacific supersonic for $1K a seat. The competition will be for the business and first class passenger paying $5K to $30K a seat. The Concorde was fast, but did not offer what we would now consider a premium class seat. The seats were small and cramped. The food might have been good, but the cabin was overheated. (Does Boom have a plan for the cabin cooling system? You could burn your hand on the SR-72 window.) It was better than conventional first class at the time if one was willing to trade comfort for time, but premium class has improved since. Now, it's more like the old Atlantic Clipper except with a mechanical contrivance to turn one's seat into a bed.
I can see a market for supersonic private jets. They'd pander nicely to oligarch egos, and the interior design could be personalized, so comfort would be less of an issue than for a commercial service. The problem is that there are only so many customers for a $100M+ private jet, and current redistributive policies are tightening things even at the high end of the asset/income curve. Billionaires who might be customers are being squeezed by a smaller cohort of ten- and hundred-billionaires, so the market is not growing.
One other point why the SpaceX comparison is not valid: a major reason for the slack in space travel is the rockets' non-reusability. SpaceX fixed that; in fact the difference between their external prices and their internal cost is probably rather large given how many "unpaid" Starlink launches they do.
Airline travel has the opposite problem, in that base prices are much too low; large airliners requires a dose of artificial scarity and a mix of seat prices to be even moderately profitable. (Or, if you're a cheapskate airline, absurd surcharges for literally everything.)
Getting a supersonic plane to the point where it's profitable, considering its high fuel consumption and running cost, esp. per passenger, will be extremely difficult, if not impossible. Personally I'd bet on the latter.
Excellent analysis, as always.
Simple question: why would anyone name an aircraft manufacturing company "Boom."
They should have thought a bit slower than the speed of sound, and realized their attempt to be clever actually elicits imagery of aircraft -> exploding.
Great post!
There’s another company called Hermeus building a hypersonic aircraft with future commercial plans. First fully functioning aircraft would be for the defense space.
I would add a fifth point to your list: Manufacture a supersonic airliner and engine in series production. Designing aircraft and engines that are manufacturable is not the same as designing a a prototype. Supersonic aircraft and engines will likely require some exotic materials. Obtaining land area, facilities, skilled work force, and a supply chain of reliable suppliers requires a ton of capital, time, and very capable management. There is also the time, skill and money required to get through flight test and certification.
Great, but not sufficiently pessimistic analysis (former P&W engineer here, from long ago). If you add "...commercially successful..." to your question, the answer is a short "no." Maybe a few private jets, if people pour enough cash onto the bonfire.
Space launches are a different economy than flying Joe and Jane from NY to Paris.
That's a bit like saying that a Nissan Micra with a good entertainment system is a competitor to a Ferrari.
The time value of supersonic travel doesn't make sense unless you earn millions per year. A decent proportion of people flew Concorde were doing it as a once in a lifetime experience. Fundamentally it's a luxury good that strokes the ego rather than a practical timesaving.
It's also a value signalling tool much in the same way driving a Lamborghini at 15 mph through the streets of London is, subconsciously people perceive that your time is worth £10 million a year if you fly Concorde, even if it isn't.
I worked at one of the companies mentioned in this post, the flying policy was basically if you were the CEOs first line you could fly private jet or business class whatever was easiest. For everyone else it was fly standard class, fly a day early and take a room in a hotel to sleep off your jet lag, get a chauffer driven car to wherever to need to go after flying but no business class. Hotels are $200 a night, chauffeured car is $100 and you cost $1000 per day, its didn't ever make economic or welfare sense to go business class never mind supersonic.
Failure cost of an airliner - immediate and reputational - has to be a lot higher than a rocket flight. Most rocket flights are considered risky. They are generally unmanned. If they do have a few humans on board, they have accepted there is a chance of death. Operating at 1 in 100 rocket flight catastrophic failure seems to be acceptable. Airlines need to be something like a million times better.
I think this is one of the few articles to get that key point that aerospace is mostly expensive because you are competing against very large incumbents who are constantly working on up-grading their product offerings.
I think the better analogy than SpaceX is Gould Racing:
https://www.gould-racing.co.uk/news
Gould will sell you a single seater car that is 95% as fast as an F1 car for ~£150k, their cars mostly race in Hill Climbs. F1 cars cost hundreds of millions to develop and run and yet aren't take much faster but it's worth it to win in F1.
I think the issue for Boom isn't going to be hitting the performance targets or even making it work. I think the issue will be making it for a reasonable cost. That Gould works being you can go out and buy a lot of the parts from a mature race car supply chain. The issue for Boom will be how often they need to pay for novel components which when added up over the cost of the plane could easily make it several times their estimated cost and thus a complete economic non starter.
One aspect of supersonic flight might strongly affect the usability of its service : time difference.
When flying East-to-West on Concorde, you would arrive at an earlier time than you arrived, which meant you could conduct business on the same day you travelled. On the way back, the same speed means that you lost a nights sleep. A supersonic transpacific flight would exacerbate the issue (losing a full sleep and arriving at a not-so-convenient hour.
First/business class seats now allow you for some degree of resting, meaning that you can fly when you sleep.
The ennemy of supersonic flight is no so much ZOOM or WiFi as it is lie-flat airplane seats.
To what extent does the business case change if the regulatory requirements are relaxed? Another business strategy famously pursued by Uber is banking on deregulation as a way to lower operating costs.
Uber was never about reducing operating costs. Uber rides cost passengers about the same as taxi rides did if one adjusts for inflation. Uber drivers do about as well as taxi drivers did. (Some would argue they do worse.) The point of Uber was to take over and unify the taxi dispatch business, and it makes its money by taking a cut of just about every ride in the area.
The ride business was fragmented. There were only so many areas where one could do a street hail. If you wanted a taxi dispatched, you had to choose a dispatcher which was like choosing a good line at the supermarket. All the "sharing", efficiency, self-driving and so on were just distractions from the real business model which was establishing a monopoly.
Actually I think people conflate Uber with Lyft. Uber was focused on the black car business model while Lyft was focused on regular people driving regular cars becoming taxis. Kalanick got fired for trying to explain that to a guy that invested in black cars while business model…and ironically Lyft benefited from the fallout. Btw, I was around Twitter early adopters and the Twitter executives didn’t plan on the early adopters using it the way they did.
That's interesting. Thanks.
Driving isn't like flying a plane. Many of the externalities which when driving are a minor nuisance (like, tired driver bumps against another car, or the engine seizes up) are fatal to a bunch of people on a plane. in this case, likely to be high-net-worth people. Say goodbye to your company's profits, if not your company.
The current regulations in the US limit aircraft speeds over land instead of limiting the actual sound energy of sonic booms. The regulation should be changed, since the speed of the aircraft doesn’t cause the negative externalities, just the actual sound. Boom Aero claims to have solved this by shaping the boom sound waves so that they reflect back up away from land and say they have proven it with the XB1 flight, but if that’s true, then they are depending on that regulation to be changed, although it’s not an issue for the most lucrative routes (NY-London/Paris and LA-Tokyo/Seoul).
Range is a challenge for SSTs, because of the inevitable range-payload-speed trade off, which is made tougher (for commercial purposes) because passengers are likely to place a higher value on cutting hours off LA-Tokyo or LA-Sydney than cutting 30 minutes from NY-SFO. As you may recall, Concorde never had the range to do transpacific commercial flights, and it was a big sales problem. A secondary problem is that when one approaches the edge of the envelope, the ability to fly long distances with a commercial payload becomes sensitive to prevailing winds--as in most days yes, some days no. It would be very annoying for passengers to pay an extra $10,000 for a fast trip, only to discover the doubtful pleasures of duty-free in Kamchatka while the plane refuels.
Range was a huge issue with the Concorde. There were only a handful of runs that made any sense at all. I was always surprised they never did the west coast to Hawaii run as it was in range, but the planes were probably full of vacationers not business travelers. (There's also the lack of a landing alternative on route.)
I'd like to know how they do that. Last time I looked the pressure cone that causes the sonic boom was a cone, i.e. it travels in all directions.
Also, Mach 1.1 is a lot more than the 1.7 which is what they currently aim for. So I'm not holding my breath on that one.
Here is their explanation.
https://boomsupersonic.com/boomless-cruise
Ah, thanks. That page does beg the question how often weather conditions are, or are not, such that a sonic boom gets reflected upwards, not to mention that Mach 1.2 is a somewhat minor speed advantage that's unlikely to justify the ticket price.
Thus they'll have to target intercontinental flights. Even so, Mach 1.7 is not going to beat the Concorde's speed record.
That would be much harder to do. I'm sure it is possible to do a technical analysis of energy levels reaching the ground, and all it would take is money for Boom to buy the analysis that it wants. I've done technical analyses, so I know that a lot of the work is figuring out the results the customer wants then adjusting the analysis to produce believable numbers in the right ball park. It's one of the reasons I left the business.
A more realistic approach would be to actually monitor the energy that reaches the ground, but this is horribly easy to game, and some parties noise complaints are taken more seriously than others.
Hmm - yeah I guess my thought was more to do with the testing and certification requirements referenced in the article. Though of course the claims about the wave shaping could actually be as a bulwark for those as well.
This might be slightly off-topic but I thought this was the best place to discuss this important issue. Is green tech growth linear or exponential? I was reading in last week’s wsj an article by j Doyne farmer who claims green tech growth is exponential. He cited that solar power is 10,000 times cheaper then when it was first used in a nasa mission in the 1970s. He also cited landlines vs. cell phones. The fact that in less then 20 years most people have gotten rid of their landlines for cell phones. But then Charles Murray the author of long hard road: the lithium-ion battery and the electric called j Doyne farmer’s type of thinking “Moore’s curse” being that Moore’s law only applies to electrics but for example washing machines it doesn’t apply. Does anyone have any thoughts regarding this?
In general, applying Moore’s law to anything other than the number of transistors on a chip is wrong. A solar cell has silicon with a simple NP junction and does not benefit from the advances in EUV lithography that are what increases the number of transistors. There are advances in production of the polysilicon used, and learning in the manufacturing processes which has brought down the cost of solar cells, but even the great cost reductions apply only to the cell. To use a cell for commercial power generation, it needs to be built into a panel with an aluminum or steel frame, glass (strong enough to survive hailstorms and snow cover), copper or aluminum wiring and connectors. Then panels need to be assembled onto an adjustable metal frame and wires together with more copper wire, and then a large inverter is needed to convert the DC voltage from the cells to higher voltage AC synchronized to the grid. The cost reductions (not from Moores law) are all in the cell itself, the glass, frames, wiring, as well as land and labor costs determine the bigger part of the cost of solar electricity, so all those graphs showing 98% reduction in the cost of a cell are just distracting planners from the actual costs involved, which will not be going to zero even if the cells were free.
We know that the envelope is a logistic curve with slow growth initially, higher growth as the economics improve and then slow growth after green energy sources have replaced most other energy sources. There are other obvious limits. There is only so much solar energy per square meter and it is highly variable. There is only so much wind or tidal energy to capture.
I think we're still in the early part of the rapid growth section of the curve. There's a lot of money in the field, and we're seeing all sorts of technical advances involving materials that could improve efficiency. For example, two layer solar panels could nearly double energy production. We're also seeing work on fuel cells and sodium batteries that could dramatically reduce the cost of power storage. If the storage problem can be solved, it could drive increased adoption of green energy.
> And it didn’t enter commercial service 1976
Typo, missing "until".
A recent WaPo analysis was succinctly titled "Elon Musk’s business empire is built on $38 billion in government funding".
https://www.washingtonpost.com/technology/interactive/2025/elon-musk-business-government-contracts-funding/
With that kind of subsidy Boom too would be better shape.
I'm not sure how popular a 1-hour flight from JFK to LHR airport will be when there's still a 1-hour commute, 1/2 hour (at least) check-in time on the departing end and another 1-hour commute on the arrival end. Sure, in NYC, you can take a Blade helicopter to JFK in 5 minutes, but you still have to drive, or be driven to, the Blade heliport at 33 and the East River, through midtown traffic, and you might get expedited clearance through check-in on a high cost supersonic flight, but all that adds cost. The projected ticket price is estimated to be around $5,000 for a one-way flight at Mach 5 (cited in Nextbigfuture's blog, but I can't find the article from a few days ago now).
That's a lot of money to save a couple of hours flying time, when there are much faster alternatives over Zoom.
I doubt that $5K number. That's on the order of what it costs to fly business class on a conventional jet nowadays. I'm sure, at $5K one way, they'd sell lots of seats for supersonic JFK-LHR flights, but I don't see how they'd make a profit except by having enough capital to sell seats at a huge loss until they've driven out all their competitors.
I would have expected that supersonic business jets would arrive before airliners. Dassault makes Rafale fighters and their latest Falcon is supposed to reach Mach 0.925.