Boom announces successful flight of XB-1 demonstrator aircraft

That would be an insane feat of engineering and probably unnecessary. Hope they don’t do that

I believe they are thinking that one is a solved problem (Jet Engine) and the other is a novel problem (Airframe with reduced supersonic noise). There has been some work done on the sonic boom problem, but not nearly as much as the jet engine problem.

They will probably just iterate from an existing engine design rather than trying to re-invent one. Just because no one is manufacturing them doesn't mean the designs are not there to be used.

But supersonic engines already exist, and aircraft manufacturers almost universally buy instead of build when it comes to choosing an engine.

maybe more so.

All current supersonic aircrafts do that. The only kind of jet engine that can take supersonic intake air is scramjet(supersonic combustion ramjet), which is more like a space age gas torch, not a turbine engine. Shockwaves are going to blow off turbine blades if not done or something along that.

Agreed I’m sure GE development very special material systems

"After careful consideration, Rolls-Royce has determined that the commercial aviation supersonic market is not currently a priority for us and, therefore, will not pursue further work on the program at this time. It has been a pleasure to work with the Boom team and we wish them every success in the future."

Guess it was a cost thing. Wasn't worth their time. Not enough customers probably.

ILS generally still requires manual visual approaches from the minimum altitude to the ground. Only ILS Cat III-C is a true autoland that can take the aircraft down all the way to the ground.

Even then, aircraft certification requirements even for Cat III-C capable aircraft requires that pilots be able to conduct a visual approach because the ILS system can fail.

An aircraft that has literally no recourse when ILS Cat III-C capability goes down (either on the aircraft side or the airfield side) does not seem like a good idea, especially because in this case large categories of emergencies are positively correlated with avionics failure.

For example an engine failure may cause power loss to avionics, so your fancy AR webcam feed is more likely to go down in that situation just when you need to make an emergency landing.

Not impossible to overcome of course - you certainly can ensure your avionics have its own isolated (and multiply redundant) power source so that it does stay up in the event of many kinds of emergencies, but personally I'd need to really see the homework on that before I'd feel safe flying in that kind of setup.

To be fair, they do need an alternate with a better visibility. But if the computers are not working, you're not in for a good time in a modern airliner anyway.

Yes and no. Line of sight was one reason, but aerodynamics was another. Pointing the nose into the wind (ie slightly down) is more efficient during landing and takeoff. Boom is avoiding the concept because it would cost tens of millions to develop and test such a configuration.

J85s are old technology. They're a turobjet, not a turbofan, nor do they have any electronics on board. This makes them highly inefficient engines. They're cheap, there are plenty lying around from old 4th gen fighters, and plenty of old guys who know how to work on them.

I suspect they used these just to get the XB-1 airborne, making progress while they find a better engine.

They have a bigger addressable market

Where would the LLM get the training data? It's not as if supersonic jet designers commonly post easy-to-ingest design data online.

Besides, most countries couldn't build a modern jet engine even if they had the exact engineering drawings of an existing one available. From fashioning single-crystal turbine blades to establishing a supply chain capable of the quality controls needed, the amount of hours spent is unreal.

That’s interesting actually - and a lot of 1950s era ‘small enough to fit in a suitcase’ descriptions (computers, nuclear warheads, jet engines…) make more sense if you realize they are a euphemism for ‘small enough to fit in a missile’. Makes me wonder what ‘small enough to fit in a cigar box’ was a euphemism for.

I mean, if you trust the math, you can just YOLO it and see what happens. The FAA is the major hurdle there though, because they don't trust the math, nor do they have the ability to really analyze it. So how far they have to go is mostly up to what they can get approved for, and how long it'll take to provide the data the FAA needs to give them the go-ahead.

It's fairly likely they'll find things that need changing along the way, which may also result in the need for additional regulatory oversight, so, double impossible to know if this will be flying at design speeds in a year or ten years or ever.

I'm sure we'll get a HN post about it when it does however.

I'm skeptical of that claim but I'll take your word for it.

It would very much be an unusual exception, in that era and now. First flights rarely even raise the landing gear, let alone push the performance envelope. Flight testing programs are designed to be incremental to manage risk as well as learn things in a deliberate vs yolo way.

Rockets are really where you see the opposite being the norm, because it's hard to do a rocket launch half way.

Effectively no! It doesn't depend on pressure. Basically just temperature (Also composition, esp: water content and form).

That relies on assumptions (ideal gas, adiabatic compression) that might break down for supersonic jets, but it's pretty close for the speed of sound.

Not an expert, but I've seen the following commented on other test flight videos: on initial test flights, landing gear is always kept down to minimize risk. If a sudden landing is needed, gear is already down, no risk of equipment getting stuck, less mental load for the pilot to perform emergency landing, etc. Basically, when testing, you want to minimize the variables being tested. When airworthyness is validated, then you can test landing gear systems.

Their website[0] does list Japan Airlines as a partner.

[0] https://boomsupersonic.com/press-release/our-partnership-wit...

The FAQ page addresses several - not all, that's why I said "look up" - of the OP's objections. OP/you might disagree (it is marketing, like you said) but they should state and explain those disagreements instead of acting like Boom hasn't thought of them.

> Not sure if there is basic/core technology development being done or valuable technology being generated. Is supersonic flight essentially just throwing a lot of jet fuel at the problem of wanting to get someplace fast? Are we expecting to see novel insights and spinoff technologies from the development of this plane and industry?

See FAQ page entries: "Will Overture use afterburners like Concorde?" and "Why did it take so long to bring supersonic flight back after the Concorde?"

> I think there's a key, core military angle to this company, where their best and most stable and lucrative customers are sure to be nation-states. I think there is some real value to be generated around super-sonic technology development for missile applications, drone applications, fighter jet applications.

Scholl indicated Boom Supersonic had no interest in a Boom product becoming a weapons platform at this time. From: https://simpleflying.com/xb-1-first-flight/

More broadly, supersonic missiles and fighter jets already exist.

> Rich people and nation states will pay through the nose

See "How much will tickets cost?" from the FAQ. Business class pricing seems eminently reasonable for this service.

> [W]asteful and extremely obnoxious technologies that degrade humanity as a whole

See "How is Boom dealing with the sonic boom?" and "What steps is Boom taking to make supersonic travel environmentally sustainable?"

In my experience, wealthy people are typically in one of two modes: 0 to 1 or 1 to 0. That's why they own both jets and yachts, rolls and lambos. Sometimes you're going fast, sometimes you're going slow, but there isn't really a need to do anything between.

> Those who care about time can already travel at much greater speeds

There is massive room for improvement. Consider the effect on global relations if crossing the world didn’t cost days but hours. More practically, consider an economy networked with this travel and transport competing against one sticking to trains, trucks and Zoom.

It's a misleading rhetorical trick to criticize a company primarily focus on trans-oceanic flights by talking about first-class domestic flights.

> Door-to-door travel times for first class...are already about 1/3 to 1/2 that of the common economy passenger on a domestic flight

What? is this a different first class? Because first class gets off the plane like 5-10 minutes faster than economy in my experience.

I was with you until the last sentence. Your train trip that crosses two continental divides is still going to take you more than a day. Even a "spare no expense" rail project isn't going to make that cross-country trip palatable for most travelers.

> build a f%@#$ train.

Until someone creates an incident on said train, and then suddenly you have to do the TSA dance at train stations too.

Supersonic is unusable over land anyway. This aircraft is designed for trans-oceanic routes, like US to Asia or Europe.

Quite hard to build a railway over the ocean.

> In general, halving my in-air time is honestly not worth a lot.

It's a huge enabler - right now, flying to see my family in Brazil is a huge PITA - two airports and 12+ hours in the air. It's less horrid in business class, but still something I tend not to do more than once a year.

If I had a 5-hour direct flight, it'd be a no-brainer.

> In general, halving my in-air time is honestly not worth a lot.

If I have a 2 hour flight then no, it isn't. If I have a 12 hour flight then it's worth more.

IDK, the degrowth, anti-progress posters are giving them a run for their money

I keep forgetting the military angle. Again a pessimistic take but when I see things like SpaceX saying point to point travel to anywhere in the world in 30 minutes - maybe the message should be 30 minutes point to point explosive payload.

It's certainly niche, but NY-LON sees ~3 million non-connecting passengers a year.

If they can make it quiet enough to be supersonic over land, it's a lot more compelling. But even being supersonic for the atlantic crossing will shave hours off of most EU routes from NY.

I think the bigger problem is the time changes on a lot of routes make EU flights pretty efficient - you don't want the overnight flights to be shorter really (and I wish most were longer).

The short answer seems to be no. Newer planes are much more efficient than older ones, but the most efficient aircraft and flight segment per passenger-distance are the A320 Neo and 737 Max making ~1000 mile flights.

Fuel burn is probably not the main reason airlines use the routing that they do.

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

The key determinant that tells you whether trains or planes are more cost-efficient is population density. If you have two cities far apart with not much in-between, then it's cheaper to build a couple of airports. If you have loads of other cities along the route, then it'd be cheaper to build a railway. The former case is true for much of North America, and the latter for much of Western Europe and UK.

If you take into account cost-per-moved-amount-of-cargo trains are dramatically cheaper, even including infrastructure. The only reason we don't use/develop them more is social/political bs not due to choosing the ideal engineering solution for the problem and that solution being planes)

As for electric flight:

1 gallon of jet fuel has like 40 kwh of energy and weighs like 6 lbs. A Ford Lightning has a battery capacity of 100 kwh and that battery weighs 1,800 lbs. Electric flight ain't happening in a big way anytime soon with current battery tech.

SAF is a good investment - it allows us to use the current airplanes while we transition the shorter distances to electrics. It also allows for a gradual infrastructure transition, because you can run a jet engine with any mix of kerosene and SAF.

And even if it runs on 100% sustainable air fuel 100% of the time, that fuel is better used powering more efficient planes.

It’s not as if we’re having surplus production of sustainable air fuel, or will have it any time soon.

Airbus lost a bunch of money developing the A380 and are understandably nervous to undertake any more high risk development projects. This is actually a great case for an aviation startup. If Airbus failed to develop a modern SST that might bankrupt them and disrupt the entire industry, but if Boom fails it only destroys a nascent startup that no one depends upon yet.

Powers was shot down in a subsonic U2. The mach 3+ Blackbird family never overflew Russia.

> Right now the regulation is a very strict "you cannot fly supersonic over the US", except military aircraft of course

I bet it wouldn't if Boeing or Lockheed managed to make their Concorde competitors.

Projections for these projects are always very optimistic. Why are you focusing so heavily on their runway being tied to some ideal date in 2 early contracts they signed?

But SpaceX rockets are not manned. You can claim success from the explosion of a rocket… Imagine this flight ended up in a crash.

Lack of an industrial base and native experience in doing so. Once one company does it, the experience gained can spread to other companies via employees moving around and forming suppliers for those same companies. For India it also has the issue of brain drain as any of the people working on India's engines could easily jump ship and move to the UK or the US and get pretty good jobs in our aerospace industries and get paid a whole lot more.

Also China does have it's own engines used in its military aircraft.

Designing very efficient engines that are also cost efficient is the focus of a lot of those big primes in the US/UK/Europe so competing with them may be difficult, however there is currently no one trying to make very efficient _supersonic_ engines. All supersonic engines are destined for military jets which care a lot more about peak performance as the primary design parameter. In other words there is no one operating in the segment Boom is trying to develop an engine and they can hire a lot of people from the rest of the US industry who already have a lot of experience designing engines or people who were trained by said people.

Ironically it may be SpaceX who kills off Boom if they're successful in implementing suborbital long distance passenger travel with Starship, though that's still very much an open question if it's possible. Such travel would, if successful, most likely be way faster and cheaper than supersonic long distance travel because of the reduced losses from drag.

in the case of India, their engine development project for the HAL Tejas started out with ~50 million USD in 1989 and had a target goal of 5 years.

Given that (even after a 650% cost overrun and 30 years) the total engine development cost is still about $400 million USD, that buys about one and a half F-35Bs.

Even when picking good and cheap, there’s cheap and then there’s shoestring.

SpaceX went from nothing to orbital spacecraft in ~6 years.

Plenty of people discounted them at the time too.

I’m not saying Boom will succeed, but it’s not outside the realm of possibility if they can dedicate themselves to task the same way SpaceX did.

I would not disagree that you can do it, but I am skeptical that you can do it in 5 years.

Honda did develop their HF118 turbofan engine apparently from scratch, but it took about 8 years [1]. And for the actual commercialization they teamed up with GE and then it took another 10 years until certification of the successor HF120 [2].

[1] scroll down on https://global.honda/en/tech/eVTOL_gas_turbine_hybrid_system...

[2] https://en.m.wikipedia.org/wiki/GE_Honda_HF120

> GE, PW, RR and I guess Safran is pretty much it.

Honeywell Aerospace, Williams International, United Engine Corporation, and AVIC are some others.

There are more than you might think.

https://en.wikipedia.org/wiki/Category:Gas_turbine_manufactu...

Not all of these make aircraft engines, of course, but a fair number of them do.

Afaik, Kratos is prototyping supersonic-class UAVs (XQ-58C and D) for military customers, so I'd expect this isn't Boom starting from zero.

So funny thing is you're in a thread about aerospace. If I might hazard a guess, discussing the concrete reasons why you think this is a scam can help educate curious readers about the challenges in this field and can probably start a discussion on the technical details of supersonic aircraft that has less emotional and more technical content.

It doesn't always work out that way though shrug.

From my own context, the work of certifying the airframe alone takes forever, let alone prototyping another engine and one that requires the thrust requirements a supersonic aircraft needs, so I too am really dubious of the timelines. But I'm curious why you think this is a scam as opposed to general exuberance, or why you think innovation in this space in particular is unlikely. There's other variables here like United's purchase; we all know companies like Theranos have defrauded established players like Walgreens, but do you think United did not do their due diligence here?

(I'm also deeply curious on why you feel that high-level criticism of the idea is relevant for this forum but the details of your criticism are not. I feel it'll teach me a lot about what motivates folks to use HN these days, but that's just my own curiosity.)

Boil-off can be prevented by loosely wrapping in 50~100 layers of aluminized mylar ("space blanket"), adding some solar panels and heat rejection panels, and a 2 or 3 stage refrigerator to keep the contents cold enough to not trigger the boil-off safety overpressure valve.

If you're clever with the orientation or possibly with a movable sun shade, you might even get by with just using space as a heat dump, by insulating against the earth and the sun and exposing to empty space to radiate the leakage heat away without a refrigerator.

I think they have enough experience with orbital electromechanical design to make this not a problem with much suffering.

There's nothing wrong with people finding sonic booms annoying. Even Boom conceded this by naming itself after its worst externality, and pretending (in its early startup phase) that it was pursuing technology to make supersonic flight less loud.

I'm sure they had mumbling nobodies back then too which the world passed by.

Their grumbling was just more limited compared to internet noise.

Boom is actively lobbying to relax those restrictions. It's not clear supersonic commercial flight is viable otherwise.

> Boeing built the 737 MAXX because they couldn’t afford a clean sheet update of 70-year old technology despite the savings.

Boeing ABSOLUTELY could afford a clean sheet replacement of the 737. They chose not to because it would have opened them up to competition and reduced short term profits. Anyone claiming otherwise is blowing smoke.

I assume you never lived under the Concorde flight path.

There will never be supersonic transport for normal people simply because the technology is unsuitable for use near people. Most people want to fly between cities and cities tend to be inhabited by people, hence the essential tension.

Supersonic flight only works for a few specific flight paths where you are flying entirely over the ocean between two coastal airports. The moment you have to fly over people those people are going to get very angry and ban you from their airspace.

Yes - now cattle can afford to fly. Soon we’ll have standing room “seats” and we will truly be like cattle.

gpt enabled pdf summarizers

>That would make a trip to Japan much faster!

Assuming it has the range. Trans-Atlantic is IMO not that interesting. You can already get to London from the East Coast same day. The continent is mostly a red-eye but that's OK in lie-flat business class. Even comfortable trans-Pacific is a slog but that takes a lot of range.

> can fly subsonic over land and go supersonic over oceans

A supersonic airframe is typically inefficient at subsonic speeds.

Sure, new technology does create new issues, and can make others worse, that doesn't mean, however, that technology doesn't also increase our ability to continue improving and doesn't make the world a better place.

Because nobody did it! Airlines are absolutely brutal businesses. Airplane manufacturing is at least as brutal. Trivia question: how long did it take the Boeing _ (pick any make) to become profitable?

It's an enormous risk to build a new airplane, to convince airlines to take a risk on you and buy it, for them to train pilots on it, etc etc etc

It's a small miracle Boom has gotten as far as they have.

Boom is not competing with Concorde!! You can't buy Concorde tickets today! Concorde was never profitable!