It should be noted that these problems aren't the only important reason why Concorde failed. Pre-orders were made in 1963-1967 and almost all were cancelled in 1973 due to the oil price shock, in addition to a 500% increase in sales price.

Concorde had a bit of bad timing. It was released during the worst crisis of aviation (until 9/11), and there was already a second version planned with increased fuel efficiency, but that came never to be with all orders being cancelled. And those cancellations also meant that all economies of scale advantages were gone.

>Concorde had a bit of bad timing. It was released during the worst crisis of aviation

It doesn't feel like Boom has the timing on its side either. Feels like we're still in a massive aviation crisis and I'm not sure how long it's gonna take before things look good for the industry.

If Boom succeeds, we'll get less expensive supersonic travel (that is going to compete against something ballistic like Starship). If Boom fails, someone will buy the tech and still use the jigs, tooling, and IP for something in the aerospace domain (hopefully). Either way, Boom folks get to work on something they enjoy and is meaningful to them (hopefully), and we all get any benefit (hopefully) from their time grinding on aerodynamics, fluid dynamics, and material science problems.

If Boom fails, it will be a glorious day for tech journalists to write the punniest headline.

I admire your restraint.

did anyone buy the jigs, tooling, etc. for the concorde?

Airbus used the new tech for their next generations of plane I believe. I guess the fly-by-wire has been used for the A320 soon after. ABS brakes, a more resistant steel alloy, there is this list in French for some of the innovation made for the Concorde and used elsewhere afterward.

http://www.club-concorde.org/ssc/ret_tech-fr.htm

Different times. Communications and financing are a different beast today. One can reach out to folks they'd never have interacted with in the old days (Twitter, for example). Someone with experience could put together 7 digit financing in a few days, 8 digit financing in weeks, maybe more.

This is one of the most interesting features (or bugs, depending who you ask) about the current time we live in. We can organize massive funding and technological efforts like this over morning coffee and Twitter banter.

I think Airbus owned them outright.

Airbus pledged to supply to tools and spare parts for Concorde until the late 2000s, so yes.

(Of course they stopped supplying them in 2003 when the service was retired after the crash).

> Feels like we're still in a massive aviation crisis

Commercial aviation tends to be a cyclical industry so there will always be a crisis somewhere on the horizon. Airlines like United are trying to broaden their offerings so that they can better maintain margins in a downturn. Some "Time is Money" expense account travelers will always have money to spend on a premium product like getting there twice as fast.

In what way is there a crisis? The major US carriers keep expanding. keep adding new routes, buying more places, etc. Air travel was at an all time high before the pandemic and is likely to rebound and hit new records in coming years.

No way. Commercial air travel is ready for a 10 year slowdown.

The main profit center for commercial air travel was businessmen going places, not too concerned how much flights would cost.

Now business meetings happen by video conference. Flying round the world for a 3 hour meeting will never be big again.

TBH, I fully expect that by the end of this year our company will resume sending management on two-week excursions every six months to Hyderabad.

Now we know how to leverage video conferencing for meetings, and we are convinced more than ever of the limitations given current technology.

In fairness, most business travel is not flying around the world for a 3 hour meeting. I do expect events, roadshows, series of customer meetings, etc. to come back--albeit probably gradually and perhaps not reaching prior levels.

"Commercial air travel is ready for a 10 year slowdown."

You're not really offering any evidence, just speculation. The actions of the major airlines suggest an expansion, not a retraction.

Are they expanding... Or are they switching towards more fuel efficient planes with the expectation that it won't be long before countries start restricting flights that produce too much CO2?

Airplanes have a lifespan. Janky "third world" countries will let you fly a plane that should have been scrapped, but the big airlines in major countries scrap their old planes at the end of life to ensure flying is safe. Getting more fuel efficient planes is a side effect (and with the cost of fuel one they are excited to get)

"never again" are such big words. Let's not assume short to mid-term shocks will automatically translate into long-term changes.

On the flip side Boeing seems to be in the middle of imploding, the ideal time for a new player to come in.

i agree with the gist of your comment, but the us government will never allow boeing to truly implode.

But if we are, as I hope, on the peak of the crisis, and Boom wants to come to marked towards the end of the decade, it could be there exactly at the time the airline industry is in the next boom.

In fact, specifically United ordered six Concordes in 1966, and canceled the order in 1972.

Plenty of time for this deal to go south.

> - Noise means you can't do US domestic

The companies working on supersonic jets are in process of lobbying hard to get FAA approval for exemptions from noise regulations. [1]

> - Concorde didn't have the range for Pacific

Not their target market, they want to be a successful niche.

> - Costs didn't work for Atlantic routes

They claim improvements in fuel efficiency and their unique selling point (apart from the speed advantage) is the use of "green" fuels (whatever that implies). Also, see previous point: they don't want to be mainstream anyway.

> - And airlines want lots of identical planes, not one special one for one route

Not a problem they want to solve. Niche and all.

While the economics are indeed questionable, these products cannot be compared to flagship products like Concorde. The jets are significantly smaller (50 PAX vs. 92-128 PAX), benefit from 50 years of progress in aviation technology, manufacturing, and operations and they have a very specific use case in mind.

Concorde was the result of a technological dick-waving contest between Western Europe and the US w.r.t. civil aviation technology. Its purpose was as much of a political nature as it was an attempt at testing/demonstrating the practicality of supersonic passenger jets.

It ultimately failed, but that doesn't mean contemporary attempts have to due to the differences in scope, technology and potentially regulatory environment.

I remain sceptical, but I wouldn't want to write it off as a failure from the get-go.

[1] https://www.aerospacetestinginternational.com/news/flight-te...

> The companies working on supersonic jets are in process of lobbying hard to get FAA approval for exemptions from noise regulations. [1]

Note that Boom _isn't_ focusing on noise currently, unlike the other companies (which are much more focused on bizjets), knowing this will limit the routes they can fly on even with any regulatory changes.

They're content to start with just the oceanic routes (and notably they're aiming for longer range than Concorde, and able to fly at least some trans-Pacific routes non-stop); presumably future iterations when it's known whether there will be regulatory changes (and what they'll be) could aim for lower noise and overland flight.

Even if they get an excemption, affected people will probably come with pitchforks and torches to the headquarter. These supersonic booms are really loud.

"Even if they get an excemption, affected people will probably come with pitchforks and torches to the headquarter. These supersonic booms are really loud."

Agreed.

I grew up near[1] the Air Force Academy in Colorado Springs and I have a very distinct childhood memory of some cadet breaking the sound barrier over our town.

I was (figuratively) knocked out of my bed. It was unbelievably loud. I thought the world was ending.

To be fair, this was probably a very low altitude flight so it was probably much worse than a "normal" sonic boom.

Still...

[1] Canon City, CO

I grew up under fairly constant sonic booms. They always seemed pretty cool because it meant a high performance aircraft was overhead. I'm sure they annoyed some people. They excited some people. And they just became mundane to a lot of people.

Are you confusing sonic booms with regular loud aircraft? Sonic booms over land are illegal in most countries. The US military only ever does supersonic exercises far offshore.

I'm not the person you are replying to, but there is a possible explanation if the person is American. In 1964 the FAA organized an experiment to perform supersonic fly-overs of Oklahoma City over a period of 6 months. Quoting from Wikipedia "the experiment was intended to quantify the effects of transcontinental supersonic transport (SST) aircraft on a city, to measure the booms' effect on structures and public attitude, and to develop standards for boom prediction and insurance data."

Link to the wiki page if you are curious

https://en.wikipedia.org/wiki/Oklahoma_City_sonic_boom_tests

Here are some highlights

- The US Airforce performed ~8 booms per day between 7am and the afternoon

- In the first 14 weeks, 147 windows in the city's two tallest buildings were broken

- An attempt to lodge an injunction against the tests was denied by a district court judge, who said that the plaintiffs could not establish that they suffered any mental or physical harm and that the tests were a vital national need

- Testing was paused for a time when activist groups sought a restraining order against the testing

- The Saturday Review published an article titled The Era of Supersonic Morality, which criticized the manner in which the FAA had targeted a city without consulting local government

- All this public pressure ended the testing early

- There were 9,594 complaints of damage to buildings, 4,629 formal damage claims, and 229 claims for a total of $12,845.32, mostly for broken glass and cracked plaster.

> There were 9,594 complaints of damage to buildings, 4,629 formal damage claims, and 229 claims for a total of $12,845.32, mostly for broken glass and cracked plaster.

That doesn’t seem much money. Even with inflation which makes it $110,600ish it seems very reasonable. I can imagine one difficult window install making up this much.

I also grew up with constant sonic booms. There is no way to mistake a loud aircraft for them. This is like mistaking a loud engine with a gun shot.

I grew up in Germany, and whatever the laws said (probably sonic booms were illegal), they didn't apply for the allied troups (mostly British and American in my region). So jet fighters going supersonic pretty close to the ground were a rather common thing, you might hear one once a week or so.

(Technically, Germany became only with the 2+4 treaty in 1990 a fully souvereign nation, formally ending the occupied state after WW2)

The U.S. military does supersonic flights over land, too. For example, see page 39 of the R-2508 Complex Users Handbook[1], the section titled "Supersonic Operations". The R-2508 complex[2] is an airspace around the area of Edwards Air Force Base in California.)

1. https://www.edwards.af.mil/Portals/50/R-2508%20User%27s%20Ha... 2. https://www.edwards.af.mil/About/R-2508/

Yeah in France we have them too, I live not too far from Mirage/Rafale air bases, and they fly over sometimes. I remember it was more common around the 2000s, nowadays I hear it less than once a year. I think it happened over Paris last year and people freaked out, calling for a bomb and everything.It was for an interception mission.

https://www.nytimes.com/2020/09/30/world/europe/boom-noise-r...

I remember hearing sonic booms while on holiday in wales as a child, just looked it up and it looks like a couple still happen every year

I assume the military can decide to be exempt from the law if they want

They can in the UK. Back in January, the QRA Typhoons chasing an unresponsive aircraft back in January went right overhead at 10000 ft at supersonic speeds. That was loud: https://www.cambridgeindependent.co.uk/news/huge-sonic-boom-...

I grew up in a remote part of northern California, and I can assure you that every so often a military jet would would fly right over our house at super sonic speeds(and very low altitude, barely above the tree tops).

It was mind numbingly loud and obnoxious-the entire house would shake and rattle and you couldn't hear anything but the rumbling.

I sincerely doubt the jet in question was flying at supersonic speeds right above tree tops. Couple of reasons, at low altitude most military jets can only handle mach 1.2 or so at the cost of massive fuel consumption. Any sort of long distance flight at low altitude, supersonic speeds would waste massive amounts of fuel. Additionally all aircraft are significantly less maneuverable at supersonic speeds which is a bad combination with being close to the ground. Lastly and probably most importantly sonic booms are really really loud. As in they can at least in theory kill people if in close contact(not aware of this actually happening at any point, but there was a cold war project to use a low flying supersonic aircraft as an anti-tank weapon). Point is if they actually where supersonic I would be surprised if you didn't have some form of hearing damage. Also shaking and rattling is not consistent with a sonic boom, just normal jet noise.

It happens accidentally from time to time. It's easier to do (accidentally or on purpose) in some planes, and engine-variants than others.

They are not looking for the ability to cause sonic booms, they are looking allow supersonic planes that don’t produce the concussive booms.

> In the airline industry’s current tube-and-wings model, shock waves largely roll off and then meld into a sonic boom. The aerodynamic X-plane, however, is designed to scatter multiple shock waves and minimize their cumulative effect, producing only a rumble or soft thump. [1]

> Acoustic engineers have developed a system for measuring sonic booms, called perceived levels of decibels, or PLdB. A decibel (dB) is a measure of pressure; PLdB is what people actually hear. When the Concorde airliner went supersonic, its window-rattling booms scored a PLdB rating of 102, equivalent, for a split second, to the high whine of a fighter engine just feet away. Those are the booms that inspired the original FAA ban. The X-59 has been designed to achieve a PLdB of 75, similar to what might be heard when standing next to a heavily trafficked road. (The numeric drop is larger than it might seem; the decibel scale is logarithmic.) In more conventional units, the Concorde’s supersonic sound waves carried a powerful maximum atmospheric overpressure of two pounds per square foot. By contrast, the X-59’s would exert 0.3 pounds per square foot on the eardrum. [2]

[1] https://www.nasa.gov/aero/nasa-prepares-to-go-public-with-qu... [2] https://www.airspacemag.com/flight-today/lower-the-boom-1809...

Let's see how this plays out. They say volume is a key factor, and the test vehicle is very small, while the plane later will be much larger.

> They claim improvements in fuel efficiency and their unique selling point (apart from the speed advantage) is the use of "green" fuels (whatever that implies). Also, see previous point: they don't want to be mainstream anyway.

That seems a logistical issue to me. Airport fueling services have Jet A/A1. So airlines buying Boom will have to arrange contracts to supply these "green" fuels at service destinations?

They've been using Prometheus Fuels (a YC-backed company with further investment from US DOE and BMW i Ventures) thus far, starting with a 2019 deal. It will probably be up to United as to how they fuel the aircraft once in service, but they are basically touting that it is using a carbon-neutral fuel source all through R&D and Prometheus is using Boom to show that it can produce A1 (or possibly JP-8 with additives) in some new ways starting with ethanol and renewable energy sources.

https://www.globenewswire.com/news-release/2019/06/18/187048...

https://www.greencarcongress.com/2020/09/20200916-prometheus...

afavour (via Benedict Evans) c. 2005

- No charging network, can't drive away from home

- Battery tech not there, no realistic range

- Too expensive, no one will pay that much for a car they can't drive anywhere

- Everyone wants an SUV or an affordable sedan, not some niche vehicle. Who's going go buy it?

Which ones has Tesla solved?

Moving an industry takes time. Will Boom do it? Who knows. But this line of thinking is kind of short sighted and defeatist, don't you think?

Tesla has at least partly solved some of those, no?

- Charging network: don’t they have their own network? I’m sure it’s not widespread enough to meet everyone’s needs, but it’s not nothing and helped get the ball rolling.

- Battery tech: has been gradually improving, range is now in the hundreds of miles which is enough for many uses.

- Too expensive / everybody wants an SUV: starting with luxury and sports models and gradually following up with mass-market models addresses both of these.

So I think the analogous questions for Boom are good and valid questions. Tesla had decent answers and Boom should too.

That's the point OP is making -- that people early on will be nay-sayers (like in the 2005 post) that then turns out to be false.

Ah, I see, thanks!

I still think the questions are perfectly reasonable. But maybe it just needs to be phrased as “how do they plan to address these?” rather than “which ones have they solved?”

> that then turns out to be false.

That then turned out to become increasingly false over time. Buying the early stage product is a risky bet, you hope it will take off like that, but it might not. They do need a plan to address them, and to be trustworthy.

That was gp's point I think, that Tesla was panned at first and solved their challenges, no reason to dismiss Boom.

Those were issues of infrastructure which weren't built out, but could be built out.

Are you planning on refueling the boom mid-air at supersonic speeds?

Tesla also took an approach that analysts who clearly weren't "car guys" weren't expecting: mainly creating something with massive HP and TQ. Previous electric cars had yawn-inducing performance. Someone buying a 5-series probably at least partially bought it for the performance, when they got behind the wheel of a model S it was like getting behind the wheel of a modified M5.

Boom isn't bringing anything new to the table to solve the issues people have listed. Tesla had a plan to solve those issues from the get-go.

Boom is bringing to the table that the technology has advenced in the last 50 years and even the Concorde might have succeeded, if a second iteration had made it to the market. Also, partially the Concorde failed because Boeing opposed it. They were working on their own supersonic plane but were a few years behind. Unfortunately, they were so successful in blocking the Concorde, that their own project failed as the market had become convinced that supersonic flight doesn't work out.

More importantly, where is the budget to "contribute" to the campaigns of enough senators to get the ban on supersonic flight overturned?

Major airlines like United have a powerful lobbying presence. If Boom starts hitting milestones, influence spigots will open.

Supersonic transoceanic flight seems like a very valuable capability in and of itself

Tesla has built a charging network, done a lot of work on the battery/range, and built an electric SUV.

So I would say they have made at least solid progress on three of them.

That's the point. Sitting at the start and saying "We're not at the finish" isn't a useful way to get anywhere

It should be obvious that the market will eventually support supersonic flights. The question is just when. OP is probably asking these questions to determine if the time is now, or in the future.

Why? What customers is this meant to serve in the commercial airline market? The Concorde overwhelmingly catered to high end business travelers, which made sense at the time. Every hour you were in the air was an hour you couldn’t be doing business. Time is money so if you need to get across the Atlantic, making the trip as short as possible was worth the price. Now we have airplanes with WIFI, we have laptops, we have smart phones. Now you can remain comfortable, productive, and connected on your flight. Secondarily was the rich persons market.

You also gave up a lot of comfort to ride the Concorde. That would be even more true today with excellent business-class options on most airlines and many world-class first-class products like the Etihad A380 “Apartments”. Are high end business flyers or rich tourists really going to trade that to save 4 hours between New York and London in high enough numbers to sustain a regular route?

There is also the exclusivity factor, but that is already highly served by private jets. Then finally, just the experience. But is that enough to fill the seats every day?

Supersonic flight is a really cool idea but the reality involves a lot of tradeoffs. When it comes down to people actually buying tickets and looking at the customer base, I just don’t see it as some slam dunk product.

There's clearly a market for it. It's just that the market is probably a very different size if a one way trans-Atlantic ticket is $5K vs. if it's $20K.

To be clear, my post was not written by me, but by Benedict Evans. I reposted it here as it felt like a worthy discussion point.

It might be interesting to see Benedict’s comments on Tesla circa 2005 to see how they compare to Boom today.

True. Updated to reflect your source

Telsa was selling hype to a lot of consumers willing to wait for perfection.

Boom is selling a tiny handful of planes.

So they have to solve these problems, largely when they launch.

Airlines are not going to run at a loss for a decade while things tune up.

No it didn’t. It sold a lotus Elise, because it was the cheapest way to deliver a car, and the MVP to showcase electric. It did not at all sell hype to consumers waiting for perfection

The early Teslas were overpriced for value delivered. They had shorter range, build problems etc..

People wanted to buy them because they were 'buying a dream' - and helping to move the ball forward.

There was a huge amount of 'good faith' in the process by early customers and supporters. Even to this day.

Tesla is an aspirational brand and people are paying an aspirational premium.

Boom will definitely be that as well. Execs will humble brag about their Boom flights, everyone will talk about - it's super exciting, super cool.

The issue I'm pointing to is scale ... will those smaller tranche of buyers be able to support all of the operational overhead of the airline and the ongoing R&D of the company ... is the question.

Honestly even if all we get out of this is an affordable low-carbon jet engine I'd call it a win. At the end of the day, Tesla is battery company that makes cars. Maybe Boom should try to be a jet engine company that makes planes.

edit: I say this as someone having little to no real knowledge of the aerospace industry :)

Elon Musk now claims that the final production Tesla Roadster used very few Lotus Elise parts. Even though the vehicles looked similar they ended up changing almost everything, and in retrospect using the Elise platform didn't save them anything.

Starting with the Elise provided a massive benefit: the ability to iterate. Big Design Up Front would have massively failed -- there were way too many unknown unknowns.

In the end the product was nothing like the Elise. But intermediate products were like the Elise, and could be driven and test manufactured and could inform revisions. A half complete scratch design could not have been.

Questionable. Going to a company that had experience with car body designs and getting an in-house designer would likely have been a better plan for them.

Many of their problem was due to the assumption that the electric car motor & batters from AC Propulsion were working as advertised and ready for mass production. That assumption was wrong. So the iteration was because changes in the propulsion system resulted in changes to the car, and changes in the car led to changes in the propulsion system.

Elon also claims that he was the sole founder of Tesla...

... after he bought out the founder(s).

It was barely an Elise by the time they shipped. So many changes were needed, that they said they'd have been far better off starting fresh, which is what they did with the S.

I don't think that would've been better. It gave them a good start for a POC/MVP.

It's the same as some people who say "next startup, I'll go straight to insert scalable architecture". That doesn't work. You need your flexibility to experiment and find what really works in the beginning.

Boom's premise is that they can reduce the sonic booms to acceptable levels while making incremental progress on fuel and maintenance costs.

Airlines are likely expecting that business trips flying coach are going to radically diminish. Offering a super-premium fast flight for the remaining business travelers who must travel but have a reduced tolerance for it is a smart move.

But isn’t Boom selling a vision for affordable supersonic flights?

What you’re suggesting about “super-premium” flights doesn’t map to what’s being publicly said about Boom or the fundamental principles of commercial flying. As a matter of fact, the Concorde ultimately failed for those very same niche-economy reasons.

What’s your source for saying that business trips flying coach will diminish?

> What’s your source for saying that business tripes flying coach will diminish?

That's an unsourced opinion based on personal experience. Zoom has become a much more common method of connecting with remote teams. I don't see a compelling reason to travel for non-critical business functions, and if the travel is that business critical then I can probably get my company to pay the expense of a premium ticket.

There are probably 2 travel occasions per year where the business travel is more of a "fun" activity such as conferences etc. I'll still fly coach for those.

In my experience zoom meetings work a lot better if you meet the people in person once in a while. Human nature is someone you know in person is more trusted than an image on a screen.

So instead of flying trans atlantic every 2 months it's once a year. That's an 80% drop in demand.

Or suddenly you realize you can be effective working over Zoom instead of in person as long as you have those couple meetings a year, so you have new business or employee relationships that only existed locally in NY or London before. That’s an X000% increase in demand.

Agreed, I thought Boom was positioning itself as “the cost of a business class ticket”, not “the cost of a Concorde ticket”.

JFK-LHR-JFK business class is about $9k assuming you're travelling fairly flexibly without a Saturday night away, at least pre-covid.

Even a month away I can't see a direct flight for less than $8k return leaving JFK evening of Jul 11th and returning July 16th.

The flights are pretty much empty at the moment, but they would be at any price. Doesn't mean that VS/DL will sell for $7k (undercutting BA/AA's $8k), it's effectively a cartel.

First of all, don't be surprised if a goal of “the cost of a business class ticket” translates into something like 50% or 100% more.

Also the Concorde was not that much of a premium over first class on, say, a 747. I'm remembering +30% or +50%. Of course, that first class ticket was very expensive if you inflate it to today's money.

Affordable is relative. International business class from NYC to London is probably going to run you $3-4K RT for a business class seat which is absolutely routine for senior business people. Assuming you consider that affordable--which it certainly is compared to a private plane--a 50% premium over that would still seem to be in the affordable category. Doesn't mean it's cheap of course.

The Concorde was a premium over sub-sonic first class but it wasn't anything like double.

I think the cost analysis was valid in the 70s when CEOs and business users were not that different from regular users.

With CEO salaries and more generally inequalities having exploded in the last couple decades I think the business model might have become viable.

Counterpoint: fast, accessible in flight Wifi is a reality now. It means that flights aren’t anywhere near the kind of “dead” time they used to be.

I’m sure some CEOs will pay whatever it costs to boost their own egos but IMO that would push them towards private jets, not a supersonic flight with United. I find the actual arguments for faster flights less persuasive than they were in the 70s.

There are far more CEOs earning ~$500k/year than there are making private jet money. I've worked for a half dozen pretty successful SMEs and all of the C-Suite flew business class and I suspect they'd all take the option to cut a few hours off their trip if it was within 50% of the price of a standard business class ticket.

For that matter, you can get into fairly large public enterprises where the CEO is making well into the millions and they are not routinely flying private for a variety of reasons--but will routinely take premium commercial.

Private is expensive. For fun I looked into it a few years ago. I never did figure out how much a share buy in was (6 figures at least), but once you have a buy in each flight is still $7000 for a domestic flight (up to 6 people same price) My entire family can fly just over 1000, though that is coach not first class. Even if you fly first class private planes are a large step up in price.

Premium air travel is also much more comfortable than it was in the 70s. First class was more akin to domestic business class today than modern lie flat seating much less the real premium roomettes on some airlines.

The connectivity probably does make a difference for some. Personally, I appreciate the disconnect time.

Being on a plane isn't technically dead time, but no matter what, it's still much more comfortable being on the ground.

And taking 6 hours total out of your flying time means you have 6 more hours to enjoy your destination. Unless I was a celebrity that would get hounded by the public, I'd rather do TSA Pre-check + first class supersonic than a private jet.

The caveat for me is that I wouldn't trust a startup that is behind its timelines to create a safe aircraft without further information.

Supersonic means you can do London-New York for a afternoon meeting in a day trip. Leave Wednesday 8AM(UK) flight, arrive 6AM(11) in New York for an 8AM(13) breakfast meeting, finish up about 1pm(18) and you're on the 3pm(20) flight and back home for midnight(UK).

According to Boom, they are aiming for fares to be the same price or cheaper than today's business class travel.

Plus I imagine many of the ultrarich that you are talking about would prefer to fly private even if it is slower than flying commercial. Flying private also cuts into the time saving benefit of supersonic flight. You save time pre-flight as you can basically drive up to the plane, get in, and be immediately ready for takeoff rather than needing to arrive an hour or two early. And private flights operate on your personal schedule which is obviously much more convenient than organizing your schedule around someone else's timing.

Private flights also go where you need to. Not a big deal if you are headquartered in a hub and have business at a different hub, but as you have business in distance places a private plane ends up a lot faster because you don't have to wait in hub airports. I know my company keeps a flight crew in Frankfort Germany so that the CEO on trips from US to India they can land, refuel and change pilots and be off in 15 minutes. (I'm not clear if the crew lives there, or just flys commercial the day before) Though if supersonic airplanes were affordable I believe the CEO makes the US-Asia trip often enough to buy one.

I think this is key. There are now a lot more rich people who would pay for the speed, and just as importantly a chance to avoid the hoi polloi, than 4 decades ago.

The Concorde actually had a pretty profitable final couple months when they cut prices down from ultra premium because it massively increased their utilization. Boom also seems to have plans for Pacific routes according to their website, so I assume they're planning their range accordingly.

Good point, higher utilization is one of Southwest's key competitive advantages since they're able to squeeze 1 extra trip for their aircraft than competitors.

Significantly cutting travel time should also enable higher utilization. E.g. cutting LA-Sydney route in half (15hrs to 7hrs) theoretically enables fitting in a roundtrip in the timespan of a one-way.

By utilization I actually meant the percentage of filled seats but yes that's also an advantage of supersonic planes. You need roughly half as many planes to service the same timetable (assuming turn around is roughly as fast and doesn't get drawn out by technical/maintenance requirements).

The Concorde basically used afterburners. It used fuel at incredible rates. Boom is using more modern engine technology that can achieve the high cruise speeds using less fuel. This also increases effective range.

So it solves 2,3, and 4. Can do Pacific. Cheaper to operate. Can be used on all overseas routes.

Concorde engines were actually some of the most efficient ones while cruising above Mach 1.7 (because afterburners were only used to take off and to go transonic until M1.7). So it was efficient but only when flying fast.

Wiki says: The overall thermal efficiency of the engine in supersonic cruising flight (supercruise) was about 43%, which at the time was the highest figure recorded for any normal thermodynamic machine.

https://en.wikipedia.org/wiki/Rolls-Royce/Snecma_Olympus_593

That's basically all fast flying planes. Engines are designed and tuned for cruising speed, not for going up to cruising speed.

The SR-71 was not exactly manoeuvrable or efficient at low speeds, its efficiency range was above M3.

Flying above the speed of sound without using afterburners is referred to as supercruise, and it is something the Concorde was capable of doing.

There aren't a lot of supercruise aircraft out there. The F22, for instance, can supercruise effectively, but the F35 cannot.

True, but in defense of the F-35 it also can't fly very far

From: https://en.wikipedia.org/wiki/Supercruise

The Concorde only needed afterburners to get to speed and altitude. They did not use afterburners for supersonic flight at altitude.

According to someone on the talk page, the Concord's engines acted as ramjets at high altitude.

Not at all, the magic was in the intake which slowed down the air so the turbojet engine could use it. And that's why it was so efficient when flying at VMAX.

Wiki again: Forces from the internal airflow on the intake structure are rearwards (drag) on the initial converging section, where the supersonic deceleration takes place, and forwards on the diverging duct where subsonic deceleration takes place up to the engine entry. The sum of the 2 forces at cruise gave the 63% thrust contribution from the intake part of the propulsion system.

https://en.wikipedia.org/wiki/Rolls-Royce/Snecma_Olympus_593

Wow. This is cool. Looks like cutting-edge technology for 1972. (Apollo 11 landing was in 1969) The engines had digital control system connected to digital sensors in the front of the plane.

It was cutting edge and in a way the Franco-British Apollo program in terms of engineering. I mean not only in terms of speed, but engines, material, fly by wire, anti skid (aka abs), carbon brakes, CoG adjustment to reduce drag, even the now common Airbus flight stick was tested on Concorde...

I remember reading a book by an engineer from the Concorde program (he's from the UK) who got invited by the Americans working on the B-1 bomber (which was initially supposed to be a M2.2 thing).

They wanted to exchange about air intakes problems such as efficiency, surges, and all. The author was not impressed at all by what had been developed and tested on the B-1. And he thought what they had on Concorde was so much more advanced (he might have been totally biased of course).

Because as people say, Concorde was not tested, it was developed (hence the many prototypes, pre-production and first production models) because a lot of the technology had to be created and if it didn't, it had to be modified to be usable on a civilian aircraft.

A classic example is pulling the throttle all the way back while at full speed: on most fighter jets of the era, you'd completely trash the turbine if you did that. So they had to create a plane which did the right thing for pilots who weren't trained like fighter pilots...

It was also a case of doing all the wrong thing in terms of management. Like assembling two of the same things on each side of the Channel to please respective governments...

>[Concorde] used reheat (afterburners) only at take-off and to pass through the upper transonic regime to supersonic speeds

The Concorde was capable of supercruise.

Note that the Concorde B (which never happened due to the eventual low sales of Concorde A) would've had no afterburners, and been quieter for climb-out and significantly lower fuel burn; it certainly was getting within reach during the time period of its development.

Concorde only used the afterburner in takeoff, and while transitioning to supersonic. It would happily cruise supersonic without the afterburner.

Still, we have had a few years of engine technology improvements since then.

Despite these problems, Concorde managed to fly for a long time... on the routes that they managed to fly.

The reasons that they stopped flying were different. It cost a lot, and was a lot more cramped than first class or private... the competition. Meanwhile, the time you spend in airports diluted the time you save by flying faster. If these could fly from LCA to a similarly small US port, speed makes a lot more sense.

That said, this will probably fail. Most air travel stuff fails. I'm hoping it won't. Progress is fun.

I don't think the size of the airport made much difference: at LHR and JFK BA had a special lounge and other arrangements. You had to arrive 30 minutes before if taking luggage, otherwise just early enough to get through fast-track security.

https://www.heritageconcorde.com/concorde-cabin--passenger-e...

Just the thought of LHR makes me want to go to bed, though admittedly, I always fly with the plebs.

LHR T5, arrive 40 minutes before takeoff - especially if you're going from a high numbered A gate for a small plane (which you could arrange for a premium service) security takes about 2 minutes, gate closes at t-20 for normal planes.

Not sure why you'd use it from Cyprus (LCA is Larnaca). If it could operate on a short runway though, London City to JFK or LaGuardia ala the BA airbus would be interesting, although the stop for Shannon has never appealed.

> Noise means you can't do US domestic

Part of that was also political. It's petty and I wish it weren't true, but a domestic-made plane making noise will be better accepted than a foreign-made plane making noise.

Whilst this is true historically, the regulations exist and I don't see rewriting them to tolerate sonic booms as a vote winner, not even for those committed to arguing against the trend towards stricter restrictions on greenhouse gases etc. A lot more people will live near the flightpaths than use them

Do you have any sources to back that up? U.S. Congress funded development of the SST (Supersonic Transport) back in the 60'ies but stopped funding in 1971 due to concerns and displeasure of exactly the sonic booms (and ozone layer issues). So five years before the Concorde entered service a domestic plane was not seen as being worth.

Heppenheimer's The Space Shuttle Decision has a chapter where this is discussed in detail.

Boom's aircraft don't make as loud a sonic boom as Concorde. Both NASA and Boom will conduct tests of this design in the mid 2020s to measure the sound at ground level in various conditions.

https://www.nasa.gov/centers/armstrong/features/how-nasa-wil...

Are you saying NASA/Lockheed Martin's X-59 is related to Boom? Or that Boom have similar goals?

NASA's flight will validate and improve the computer models that Boom is using to design their plans.

Is this a stated plan of Boom's (in particular, with regard to noise), or speculation?

Boom's page on why their aircraft won't have the same fate as the Concorde focuses purely on (fuel and route) economics, not noise [1].

1: https://boomsupersonic.com/flyby/post/will-boom-supersonics-...

This video doesn't mention sonic booms, nor NASA, at any point.

Boom talks about

- much lower noise than Concorde (mentioned elsewhere in this discussion). Ironically, they reduce the "boom".

- Pacific crossings. 4,900 miles range ( https://onemileatatime.com/boom-supersonic/ ) Tokyo - Seattle is about the furthest within that, at 4,777 miles. California to Hawaii is easily in range, USA to Australia is far out of range, but Brisbane to Hawaii is in range.

- Article talks about 15 planes not one.

Have they solved those yet? They're not flying yet, so no. But that's what they're aiming at.

> Tokyo - Seattle is about the furthest within that

There's about the shortest viable route I can imagine. I could see refueling stops being a thing, though. SFO-SIN is a pretty long flight, so an hour to refuel in Tokyo wouldn't be so bad.

> There's about the shortest viable route I can imagine

Right, this (Tokyo - Seattle) seems like a minimum viable Pacific crossing.

San Francisco to Tokyo is 5,133 miles, so it is out of range.

How about San Francisco to Hawaii, Hawaii to Tokyo, and Tokyo to Singapore. ;)

To actually answer your questions:

- Noise means you can't do US domestic

They don't seem to be targeting this.

- Concorde didn't have the range for Pacific

They do seem to be attempting Pacific range.

- Costs didn't work for Atlantic routes

They are trying to bring down costs considerably.

- And airlines want lots of identical planes, not one special one for one route

This will certainly be a drawback, although if they could take e.g. 50% of premium transoceanic it won't be so specialized.

The world is also a lot richer now than it was in the 70s. Some luxuries that didn't make sense 40 years ago may make sense now.

> - Costs didn't work for Atlantic routes

> - And airlines want lots of identical planes, not one special one for one route

On both of those, the passengers are kings. If enough people decide they want to pay a lot to cross the ocean quickly, those things will not be a problem.

These three (albeit somewhat long) videos answer a lot of the questions you asked:

Flight of the New Concordes - https://www.youtube.com/watch?v=lZLykryZLFk

Supersonic Planes are Coming Back (And This Time, They Might Work) - https://www.youtube.com/watch?v=4p0fRlCHYyg

Supersonic Flight - What Does The Future Hold? - https://www.youtube.com/watch?v=N3K04wgf_ZQ

If the plane goes supersonic at 10 miles of altitude, will it still make much sound on the surface? It's not just distance, it's the pressure of the air at the altitude, too.

Haven't engines improved a lot since 1967?

No idea about cost, but currently oil is cheap and abundant, compared to 1970s, and the U.S. has a large domestic supply.

Regarding identical planes, I suppose first Boom's supersonic planes are going to be mostly identical. But even standard airliners get small changes with every dozen planes built.

you forgot another big one the Concord faced: cosmic radation. The plane carried a geiger counter.

https://en.wikipedia.org/wiki/Concorde#Radiation_concerns

But even if you get a higher dose per unit of time, you spend less time in the air so your overall dose is lower. Your link mentions that. I guess the main exception would be for personnel that did a lot of flights. That could be reduced by requiring longer ground breaks than with subsonic aircraft.

The amount of radiation you receive during a regular flight is quite small, and more than you would receive on a supersonic flight: https://youtu.be/TRL7o2kPqw0?t=307

Right, that's something I was wondering when Boom was announced a few years back [1]. Will radiation be even worse for the crew if the plane body is made of carbon-fiber vs thicker metal like the Concorde was?

[1] https://news.ycombinator.com/item?id=12791122

> Costs didn't work for Atlantic routes

Common misconception. The Concorde was absolutely quite profitable throughout, and massively so after they adjusted the prices down at the very end when it was already being shut down due to safety reasons.

safety reasons? There weren't any safety reasons.

The Concorde was the safest plane ever. It flew for 27 years with just 1 accident. And that accident wasn't Concorde's fault. Another plane dropped metal on the runway, and Concorde ran over the metal and got damaged right before takeoff.

There are individual passenger aircraft that flew more hours and cycles than the entire Concorde production run without incident. The accident where running over a piece of metal on a runway during takeoff resulted in a raging inferno and ultimately the deaths of everyone on board wasn't the first time Concorde's unusually-prone-to-failure tyres had punctured a fuel tank when they exploded, or something likely to happen if a different aircraft ran over the same piece of metal. Separately, it also had two spontaneous in-flight structural failures of the rudder. All this in a production run of 14 aircraft that spent most of their life on the ground.

Considering it was a complete novelty designed in the 1970s it did OK, but I don't think there are many airframes its safety record compares favourably with.

They create a PR boost for United. They can tell the business travelers that "Super Diamond Elite" business travelers will get first access to these flights (Dates TBD). Making those people more likely to go with United over Delta.

I made this comment earlier, but Wendover has a great video on this very topic: https://www.youtube.com/watch?v=4p0fRlCHYyg

How many transcontinental flights fly USA domestic routes? If this can cut my flying time from Seattle to Beijing, I would be a happy camper, hopefully they can go boom over BC, Alaska, and the Russia Fareast.

No wireless. Less space than a nomad. Lame.

That's not really an apt comparison.

When iPod came out there were numerous successful portable music players already on the market. The iPod skeptics were not skeptical that there was a market for a portable music player--they were skeptical that the iPod's particular combination of features and limitations would do well.

With supersonic passenger service no one has demonstrated that there is actually a viable market for it. The two prior attempts were both heavily subsidized by government (Russia for the Tu-144, France and the UK for the Concorde).

It is quite different to ask "why do you think this product will do well against a bunch of established, viable competitors?" and to ask "why do you think this product can succeed in a market that everyone who has tried before has failed in?".

IIRC Concorde development was highly subsidized by the government but it became a sustainable business for British Airways as long as there were wealthy business travelers willing to pay a huge premium to get between the financial centers of NYC and London in 3 hours. After 9/11 a lot of that business went away and Concorde wasn't viable anymore.

Boom is taking the government's role, not BA's. I once did a back of the envelope calculation which suggested the government could have lost less money paying for a NY- Europe business class ticket on a regular aircraft for every person ever to fly Concorde. It was as spectacularly bad commercially as it was impressive technologically.

It was a sustainable business for BA because they got several aircraft at giveaway prices (the minister who sold them conceded it may have been the worst deal ever negotiated by a government!) which they could charge extortionate rates to fly on, but they still weren't flying more than one of them at a time very often.

You could add: - Concorde didn't work flying east because with the time zone thing, you might be flying real fast, you still arrive super late. Meaning you could as well pay less and fly the red eye...

I fly SF->NYC redeye regularly. The practical side of takeoff and landing is that I get 4 hours of sleep max. I also start to sleep around 2AM NYC time. If I could reduce flight time to 2.5 hours, I would rather land in NYC at 2AM and get to bed there so I can start my day much better rested.

But do you fly in first class? Because for cheaper than Concorde, that's what you could get (and that's what Concorde was competing against) and usually in first, they don't wake you up for breakfast or whatever before you land...

And the other issue in your case is flying supersonic over land but I hear you.

First class is all very well, but you don't escape the unfamiliar bed; the noise of the engines and other passengers; the weird air pressure; the fact you're in your travel clothes; the strangely corporate environment; or the jostling and noise of landing and takeoff.

Of course, some people are less sensitive to these things than others - and jobs with a lot of travel probably select for people who find the experience of flying tolerable.

Yes I do and they absolutely do wake you up before you land. It's an FAA requirement that the seat be upright.

it might be an FAA requirement to be upright, but iirc some other international airlines (eg. virgin atlantic, air new zealand) allow you to keep your biz class seat in seating position during takeoff and landing.

At some point, I decided I'm too old for redeyes unless I really have no choice. Yes, it means getting up early to get in at a reasonable time but at least I sleep in a real bed.

I've flown London to Washington DC for meetings and then immediately returned to the airport to fly back, and I'd have loved to have had the ability to fly supersonic for trips like that.

So while "just" flying East might be less attractive, very brief return flights will be attractive even if one of the legs doesn't seem very beneficial.

There are plenty of scenarios cutting hours off will improve. Whether there are enough of them to make Boom profitable is another matter.

I think Concorde was profitable - at least for British Airways.

Well, yes. If you ignore the development costs, British Airways turned an operating profit.

Same with Air France, Concorde got profitable with all the special flights (supersonic loops, world tours and all these).

Can’t you do coast-to-coast? I thought the requirement is no sonic boom over land, but you can fly out over the ocean and then turn around at Mach N. Eg SF<>NYC would be an obvious route that is worth adding some miles at the start, if you can go 3-4x quicker.

A sonic boom is a continuous noise, not just at the transition. You perceive it as a single noise at the ground, but so does every other person along the entire flight path.

Boom's aircraft uses a modern design that reduces the loudness of the sonic boom.

Thanks for the correction, I did have that incorrect. TIL.

Interesting follow-up -- from https://en.wikipedia.org/wiki/Sonic_boom, the angle of the shockwave cone decreases (i.e. gets narrower) as the plane's velocity goes up. I'm wondering at what Mach number would the cone be tight enough that it doesn't intersect land?

The boom happens whenever you're flying supersonic, not just when you transition from < Mach 1 to > Mach 1.

I hope everyone is given flight suits as just the image of a plane full of people making a 180 degree turn at 600mph to accelerate to 740mph is somewhat comical. I know not entirely what you are suggesting but its immediately the thought that came to mind.

The plane might not be efficient at subsonic or transonic speeds.

The biggest problem is that supersonic just steals first-class passengers from other routes, where the profits are higher.

Also, far higher climate impacts, which is what concerns me the most. Lets just be happy with crossing an entire ocean in 6 hours.

While you are canabalizing some of your own 1st class passengers, the first airline to get a supersonic route going will also take first class passengers from other airlines.

You mean the third airline? This has already been tried before, and the financials didn't work out the first time. Maybe everything has changed, but who really knows.

And frankly, I'm hoping for failure. Some of these new super-sonic companies are trying to get approval for continental routes, saying that the boom is only as loud a car door. Like a car door slamming shut for 3000 miles is no big deal. The super-wealthy have enough toys to inconvenience the rest of us and destroy the climate; they can keep hanging out in first class, or on their private, subsonic jets.

When I read the headline I was quite confused at first, a big why why why? Then it came to me, it's a business bet on wealth concentration. Conventional first will always be far more comfortable, private far more convenient, but supersonic easily outdoes them both in bragging rights. And think of the networking opportunities when (if?) passengers are almost as packed as in coach despite paying a huge entry fee!

And the environmental aspect won't feel too bad actually: if you are traveling first you produce x times as much CO2 for your trip as others (how many more could they take aboard if that are was as densely packed as regular?), only because you are, well, too soft to sit out a few hours. But if the CO2 happens because supersonic, you get something very real in return. Time! Who could blame you?

The first one (or at least aspires to).

Do they? The FAQ suggests that they are not aiming to do supersonic flight over land:

> Won’t the sonic boom be loud?

> Overture flights will focus on 500+ primarily transoceanic routes that benefit from supersonic speeds—such as New York to London or San Francisco to Tokyo. Overture won't generate a sonic boom over land cruising at subsonic speeds.

So what are the other 497+ possible routes (new York Paris also works) ? I read somewhere that after a Concorde test flight to Singapore, India complaint strongly and stopped the airway.