The blog post is hyper focused on the wings and didn't make a lot of sense without context. This link[1] was extremely useful to better understand what Boom is doing and how far along they are.
But the first image really sucked. The other 30 images and animated constructs were super cool, but the entire experience was wrecked by the first image that you see, which looked like a jpg of a plane drawn in ms paint.
This is probably a dumb question, but if the wings are now closed forever, how does one do maintenance or inspection of the mechanical flight control systems composed of cables and pulleys? Is the expectation that the XB-1 is going to be used in flight for far less than the design life of those mechanical systems?
Aluminum aircraft go together more or less the same way. There will be some inspection panels but the interesting stuff is already exposed, there's very little reason to go inside the wings, particularly on a composite aircraft where corrosion isn't a problem. If you really need to see something, use a borescope.
You can see in the article that now no cables are in there during closing, they are in extra canals/tubes which can be accessed later on, be it for installing them in the first place or maintenance.
They probably use an electrified system with wiring and servos, levers and push rods. Prior to that we used hydraulics. These parts are probably accessible with removable panels.
If they had, they'd still have mechanical pivots and so forth that can wear, but the article specifically mentions pulleys and cables:
> The team also inspected flight control pulleys and cables, which are routed through the wings to the systems bay, as well as the aileron trays on the outboard portion of each wing. (Ailerons are the hinged part of each wing that control roll or maneuvers, and are controlled by the pilot via wire pulleys that run through the wings.)
I suppose that the cables have to run out of the wings and into the cockpit in order to be useful, and that you could put you adjustments for cable stretch, etc in a place you could get to them easily. Or add access panels, as you suggest.
Yeah as I was reading this, all I could think about was how there was no serviceability or reproducibility, the focus was on just building it, probably within a weight budget. There doesn't seem to be any long term breakthroughs or industry advancement here as all applications are specific to this model. By sealing the wings forever you are sort of guaranteeing steady business for the fabricator's check book as new ones will have to continue to be built for whenever there's damage (ground strike, etc).
This is quite scary for a non-engineer. You're telling me that this little supersonic plane has the whole wing structure held together by a handful of 4mm thick metal struts, manually glued to the wing surface, with wire pulleys running on the inside :O
Building a plane in my garage. You'd be surprised how minimal yet how strong a lot of these structures are. The vast majority of the material I use is thinner than a credit card.
I want to hear more about building a plane in one's garage. Are you using a kit? How hard is it? Cost? How will you transport it to an airport once it's finished?
Kit: Yes, in my case it's an RV-8 by https://www.vansaircraft.com/ they're probably the biggest name in town by volume and they make mid-cost kits. There are some more and less expensive options however.
Hard: I took a class from a licensed A&P mechanic and while not mandatory, gave me a pretty good idea of what I'd be up against. It is extremely challenging even with a kit however. Lots of learning, lots of redoing stuff because of mistakes, many many hours.
Cost: whatever you want it to be really. You can do safe builds probably from around 40-50k for something like a Sonex or Kitfox to several hundred thousand for a Velocity twin or even something turbine powered.
Transport: most people build in their garage and leave the wings off then stick it in a trailer or U-Haul to complete final assembly at a hangar. It's mostly a non-issue.
Kits have become progressively simpler to build. The example like the RV below would conservatively take over 1500 hours. A newer Vans RV-12, much less. A Rans S-21, possibly 600 hours. Looking at their wing build:
dramatically simpler than an RV-8. My -8A flying cost was about $75K a decade ago, it would probably take at least $90K today. An S-21 would probably be more.
Some kits come with a folding wing option, so they can be trailered.
The primary decider in the difficulty/time factor is community and your Technical Counseler [1] (usually a multi-kit builder and FAA approved). If you’re able to build near a very active community (Livermore has a lot of RVs), these people will show up at your house/hangar and get/keep you going. Amazing people who can teach you a lot.
Glue is sort of the wrong word. When you hear glue you maybe imagine the general purpose glue that you can buy, like Elmers glue or Super Glue. This is a chemical adhesive designed specifically for the surfaces that it's holding together (i.e., they will use a different glue for composite-to-metal bonds than metal-to-metal, etc.) and it's very strong.
Many things you wouldn't expect are glued together. Many weld and rivet connections on cars have been replaced with glue in the last few years.
Various reasons. Chemical bond glues are only strong if there’s something for them to bond to; it’s expensive glue; it’d be much harder to make the entire plane out of that stuff, especially given the desired tolerances; sometimes it has other problems that make it unsuitable, e.g. how it reacts to environmental conditions it’s exposed to; it’d look and sound silly…
Traditionally in aircraft design, you can't rely on adhesives for primary structural integrity. It's mainly because it's hard to ensure you glued right, it's hard to inspect.
Also we don't like it too much because it's harder to repair.
Adhesives are used, but normally for secondary structure, or as reinforcement to fasteners. So for example you'd ensure that a failure of the adhesive wouldn't lead to catastrophic failure, but it may lead to early cracks that would be detected in regular maintenance.
In the case of Boom they seem to rely more on adhesives than the traditional airframe methods. At the same time they are making a one-off demonstrator here, so they can afford to choose methods that need particular care and inspection, even if it would be unrealistic to expect that level of quality on a real production line.
Yes, glued. Although "structural adhesive" is the preferred term. Race cars and carbon fiber supercars are built this way too, there is decades of experience in this kind of manufacturing for high stress environments.
"It’s the following morning and bonding appears to be successful, but it’s essential to confirm that the bond lines are shaped correctly or “filleted.” A member of the engineering team, who is certified in the process, begins non-destructive tap testing to audibly listen for voids such as air bubbles within the bond. With several decades experience, he knows what to listen for. Using specialized tools, he taps all bond lines and listens for different and unusual noises. He confirms that bonding is a success."
In general it seems that their main fabrication cost is labor, and it would probably be very hard to scale for production. I wonder why wouldn't they choose titanium - the price of material doesn't seem to matter here, and while it is hard to work with than say steel, i'd think it is still more mass production friendly than carbon fiber.
One issue with Ti: Tooling costs, particularly for manufacturing skins. Tooling for shaping metallic skins to the required dimensions is fantastically expensive, which can be prohibitive for prototypes. Carbon fiber can be shaped much more inexpensively.
BTW, "scaling for production" in aerospace doesn't mean a tremendous amount of units, most of the time. Lotsa carbon aircraft running around have been built in a manner not too differently from this one. So those labor costs tend to work out okay.
For a while I did repair design and analysis for engine nacelles made out of carbon fiber. These were new parts, right off the production line, with various flaws that commonly happen when you make an airplane out of cloth and glue. I was amazed by how much manual labor can go into declaring a particular part flight-ready, and the financials still penciled out, apparently. We must have been well into the six figures on one particular nacelle in post-fabrication engineering analysis work, just to show that the flaws had been repaired adequately for entry into service.
Originally, the F-22 was going to be built mainly of carbon fiber, this was changed to titanium to reduce cost. This was in the 1980s... CF is MUCH cheaper today and almost commodity material used extensively in civilian aircraft.
And it would probably interest OP to know that it's not just basic strength-versus-mass where carbon shines. With metallics, you have that strength in every direction. But most parts only need to be strong in a limited number of directions. With carbon, you can tailor the part to provide strength only in the directions needed, which means you're using less material. More weight savings on top of what you already gained* by switching to carbon in the first place.
[*] It ain't all sunshine and roses. Sometimes it just doesn't work out. Substantial strength reductions due to heat and moisture absorption are real. Other factors exist that'll ruin your weight savings too. A former boss of mine designed a carbon nacelle inlet lip for a popular airliner, but it was a short haul aircraft, which means lots of trips, which means lots of abuse from careless ground handlers. After accounting for that, it weighed as much as his reference aluminum design. The nacelle went into production with aluminum inlet lips.
Ultrasound inspection is very common for multi-layer composite construction. There are large machines which transmit the ultrasound through a water jet, for use in mapping the characteristics of curved surfaces. This water jet ultrasound non-destructive testing (NDT) is used in aerospace for carbon laminates.
That said, 'tapping' is an acoustic inspection technique, and can get good results.
I am not sure why they selected the manual option, but they probably have a reason.
They're probably having the guy hit it with a mallet and listen for voids because they're a Mickey Mouse operation by aerospace standards. Plus this is a model so if something does go catastrophically wrong it at least won't kill anybody, probably.
yes, ultrasound on ship welds, and if i remember correctly - on some forged and other way fabricated/processed parts too. X-ray on even more important stuff like nuclear plant welds ("China Syndrome" has nice depiction around it).
We do mostly structural steel at work. Some jobs require all welds to be inspected using ultrasound and magnetic particle tests, so we weld to that standard pretty much all the time on every job.
Somewhat OT - but from their FAQ they say they're targeting a price of $200M for the Overture. I'm certainly no expert, but this feels to some extent a bargain given the capability. Capacity 55-75 passengers. A few data points for comparison (all of these approximate of course, with multiple variants available of each):
Airbus A220 - $90M
Airbus A320neo - $110M
Boeing 787 - $140M
Boeing 777 - $320M
Airbus A350 - $325M
Gulfstream G700 - $75M
All of these can of course carry more passengers (except the Gulfstream), but assuming it's somewhat efficient from a fuel perspective, and assuming an airline could sell ~60 business class seats on each leg, I'm optimistic for them - cutting your trip time in half is certainly something to brag about.
For reference, as an example, a British Airways 787-9 used for transatlantic routes seats 8 first, 42 business, 39 premium economy, and 127 economy.
The Concorde was a thing of beauty. Massively expensive to produce and run, and fuel inefficient, it was a passenger airliner that could outrun fighter jets. Fighter jets of that era could get to mach 2 using afterburner, but that's especially fuel inefficient so they could only keep up for 15 minutes or so. The money that went into the program (which is estimated in the neighborhood of $10.3 billion) was later recouped in the form of expertise that went into building Airbus.
A lot of time has passed since 1965 when the Concorde was first produced, and the improvements in technology (especially for materials) since, will hopefully allow the economics to work out better this time around. But with the rise of lie-flat seats and personal entertainment systems, flying business class is "good enough" compared to the surcharge that flights on the Concorde cost, so I'm cautiously optimistic.
Taking 3 hours instead of 6 is better, but still not low enough. Add getting to/from the airport, and checking into the hotel and all that, you're still out the better part of the day.
The really pie-in-the-sky way to travel is if a certain reusable rocket company ran (exorbitantly expensive) passenger service. Moscow to New York in 30 mins, or Moscow to London in 15.
<=3 hour flight time kind of sucks, because you're spending additional 1-2 hours at the departure airport and at least 30 minutes at the arrival airport. Then there are the trips from and to airport which are often 1-2h. Then there's scheduling slack, which translates to additional ~20% wait time. When flight time is 3h, you're expecting to spend 7-12 hours. Usually closer to 12, because you'd rather wait longer than run the risk of missing one of the transports.
One of my great travel-related discoveries has been that if I can find a train that takes even about the same amount of time, it will always be much more pleasant and less energy-draining than air travel.
All so true. The actual flight time is a non issue for me given the hassle of the airport. But I’m guessing this is for higher end travel, where skipping lines is the norm.
I once had the opportunity to fly a business-only airplane. There was no line skipping. There was a whole dedicated terminal for these airplanes. As soon as you entered the terminal someone would welcome you like at some luxury resort. The passport and ticket thing was a breeze, then they would guide you to the lounge, if you were early. If you timed your trip accurately, I guess you could find yourself from the terminal door to sitting in your comfy seat within 15 minutes. Champagne glass on the tray in front of you, of course.
>I'm optimistic for them - cutting your trip time in half is certainly something to brag about.
I wonder how the economics works out. We know consumers are willing to give up a lot of things for cheaper tickets. And for that market it is now a volume business.
Business Expenses and trip could certainly paid for super fast airline. But this could cut out business trips revenue from normal operation, so it means flight price would have to go up to compensate for the loss of business class?
Although I am pretty sure they will sell well for as a private jet. Most super rich has way too much money and too little time.
I don't think it will cut much revenue from regular business class, rather, it will cut from "first class" (which is on its way out for most routes) and from last minute tickets.
Additionally, if you cut your trip time in half you double the number of trips you can take. This is why the metric is Available Seat Miles. In a way it's like making a plane with a capacity of 110-150 pax.
Having been following BOOM for years this thought never occur to me. I thought BOOM was the sound coming out of the engine signalling ultra fast / super sonic speed.
What is annoying is that Now you have mentioned it I cant get that "crashing" thought out of head.
And that's also one of the big reasons that supersonic passenger aircraft have failed in the past - restrictions against supersonic flight over land due to the extreme noise. It seems strange to me that Boom would want to draw attention to this in their brand name!
The whole premise of the startup is to build a silent supersonic airplane. Building atop several years of existing research and experimental programs around silent sonic boom.
When I was a kid I had these crash test dummies toys with a test car you ram into wall. That immediately sprung to my mind and I had a good laugh and a good reminisce. Thanks for that. Here’s a silly commercial for the car and toys. I honestly think they made me a more defensive driver years before I got behind the wheel.
The level of care and organization in this photo feels equivalent to what I would expect for a ground robot prototype out of a startup. Can any aerospace engineer comment on what they see? Does their setup inspire confidence?
It looks normal. Our shop (assembly line building full aircraft from material stock, 2 football fields long) was like that except most of the workers were filipino or hispanic, wearing street clothes. When they filmed a TV commercial there, they brought in actors wearing red jumpsuits to scurry around as technicians. Because like you, that is what the public expects.
I've seen many of Boeing's wing assembly lines and there are a lot of similarities here, except that this is clearly not set up for mass production. (Which makes sense for a demonstrator.)
Also from the startup ground robot prototypes I've seen (and made) this looks much neater and more planned out than what's normal.
I noticed that too. I loved the caption on the second photo: "The closeout process is relatively simple, yet requires the highest level of precision possible." LOL. If you look at the picture, one guy is moving a chunk of rough cut lumber, another guy seems to be eyeballing it, there's stacks of plywood sitting there, hand clamps with wooden shims, wires dangling and a bunch of strips of tape with hand written arrows on it.
I'm sure it's all very highly technical work, but that caption and photo was hysterical.
I like the idea of supersonic passenger jets existing again. I'm not sure I really see the point though.
Would you rather fly in business class comfort for 8 hours or with less comfort for 4 hours? Almost doesn't seem worth the expense and risk of going supersonic.
I would be so much more excited about an airplane that was large enough that economy class seating was as comfortable as business class seating is today. That would be much more revolutionary.
I would also get excited about an airplane that was vastly safer than the already-quite-safe airplanes we have.
An airplane with a fail-safe fuselage that can disconnect from the rest of the plane, parachute to the ground and land (or float) safely. This could potentially eliminate fire danger by jettisoning everything flammable (gas filled wings, engines, cockpit, and whatever else).
The fact that flying is uncomfortable and still-too-scary to millions of people are the biggest opportunities for innovation that I see.
Flying at 500+ MPH is already quite fast given the size of the planet.
> An airplane with a fail-safe fuselage that can disconnect from the rest of the plane, parachute to the ground and land (or float) safely.
The thing is, the vast majority of airplane crashes happen at takeoff or landing, because that's when there's the least time to react if something goes wrong. Unfortunately, this is also when a parachute would be least effective, because there isn't sufficient altitude to deploy one. (Never mind that we don't even have a design for parachutes large enough to safely land an airliner fuselage.) Additionally, by giving the fuselage the ability to separate from the wings, you seriously weaken the strongest and most critical point of the aircraft: the main wing spar. In other words, you gain an additional risky emergency landing method, which could only be deployed in certain very unlikely circumstances (if the plane is high enough to safely deploy parachutes, it it probably high enough to glide to a safe landing, or at least safer then landing wherever you end up with parachutes) - and in the process you also now have a much higher chance of the wings falling off in midair.
Single day round trip flights New York to London for business meetings would be a big seller. Leave NYC at 6am, get in at 3pm London time, have meetings till 7pm, get home at 8pm New York time. No jet lag and sleep in your own home. Huge value.
Not sure how you can desire better safety. The last fatal crash of a US airline flight was in 2009.
So far this sounds more 'affordable' than 'business class comfort' which I STILL cannot afford no matter how hard I try to justify it to myself.
There's gotta be a market for an all-business-class plane, since we know that first/business subsidize coach, but nobody's doing it yet. The airlines want to throw those business class seats out as perks to people spending corporate dollars, not charge the end user what they actually cost, in which case "real humans" could afford them.
Wow, cool! Of course, I tried to get more info on pricing and following the booking link took me to a "Generic booking" page which, even flying into JFK and out of LCY, didn't show me the option, but I'd be really curious if I lived in NYC, for sure.
I've also had this issue with the "Premium Service" United flights between SFO and NYC/BOS. It supposedly exists, but whenever I search, I can't filter on those particular flights.
>I would be so much more excited about an airplane that was large enough that economy class seating was as comfortable as business class seating is today.
there is really no point where it becomes worth it to make seats bigger without charging more. If there is more space on the plane, it makes more since to put more seats there, not keep the number of seats the same
There also exists a Boom rival - Spike Aerospace[1]. They successfully completed and operated flight demonstrators (SX-1) and working on delivering a production plane now.
There's something a little sketchy seeming about Spike if you look at their website. The Boom demonstrator in this article is a real, hopefully supersonic aircraft with lots of photos etc, but Spike seem to have zero photos of the SX-1 which is/was apparently a subsonic radio controlled aircraft.
How can spike say on their front page "The Spike S-512 is the only supersonic jet in development that will fly at twice the speed of other jets without creating a loud sonic boom." Boom is also aiming for 2x existing jets without sonic booms. That's wrong, misleading, is there some narrow explanation for how that could be accurate?
This test plane has a range of 1k nautical miles but a cruising speed of Mach 2.2, which works out to like 40 minutes of flight time at max speed? That seems like a really tight window for takeoff + test + land + any kind of safety buffer. I'd be curious to know how they handle those logistics.
They have a safety reserve of fuel. They fly it in the desert so they can glide to a landing anywhere. And plenty of your time will be below max speed (since air resistance is non-linear, your fuel consumption is much lower during these times).
Does this mean if any repairs are needed they'll have to rebuild the wing from scratch?
I'd love to hear from someone at Boom what the main goals are for this aircraft. And how it will differ from the larger transport craft they're planning. Beyond size and capacity.
The company's goal is overland supersonic flight. Profitably, ideally. To make that even a legal possibility means demonstrating they can be somewhat quieter than prior supersonic aircraft. This aircraft is a proof-of-concept.
Is it specifically to demonstrate that they can make a quiet aircraft then?
I think I'm curious specifically whether this is more about internal R&D and building systems, or if it's meant to demonstrate they have the capability to to create a performant supersonic aircraft, which they can take to potential investors.
Any idea how often the final design and the prototype don't match in terms of volume and aerodynamics? I would have assumed that those parts are the easiest to model with high confidence.
You don't need to build it to test volume and aerodynamics (math and wind-tunnels can figure that out for you). This is probably more about finding unknown flaws in the design/running down risk. Spending however much on a prototype (10s or 100s of millions of dollars) just to marginally reduce the risk that there's a fundamental flaw in your approach makes a lot of sense when you plan to spend 6 billion total to develop the plane.
Depends on the event. I've never heard of anyone doing an xray on hangar rash type damage, at least not within a part 91 environment. Taxiing into a pole would be a different issue however.
Are there other industries like supersonic and space flight where a competent startup could attract top engineers in the field from government and academic jobs? (This question is partly rhetorical. If you have a good answer… Go do it!)
Having built a glass/kevlar/epoxy kayak, it's a little mind blowing to read about people building a supersonic airplane, using similar (albeit far^N more precise) techniques.
Did you build a pygmy kayak kit by any chance? I did, it was the most fun I've had building something in my life. The entire "epoxy plus fibrous material" is truly a winning solution for so many applications, apparently hyper-sonic wings, too!
No, this was a high-volume play boat. About 35 years ago. And it wasn't a kit. I was boating with a club with a shop, and members who knew what they were doing.
The F-35 is also low-observable. I'm a total lay-person on this one, but I'm betting that the tolerances for achieving flight (even at Mach 2.2) are a lot looser than the tolerances for being invisible.
Yeah, the F-35 is actually milled down during/after assembly for low observables. However, the Mig-21 can hit the same speeds as the XB-1 and it has panel gaps visible from several meters.
I did some reading and the XB-1 does use hydraulics. From VEP and other companies.
It looks like they will be using titanium leading edges to handle the heat loads.
They are using a J85-GE-15. I don't think that will allow them to reach M2.2. Closer to M1.7 or so? Depends on the inlets I think.
(I was wrong on the engines. They are using 3x engines, not the 2x afterburning that I was expecting. So the speed looks reasonable)
Pilots have a better chance of saving the plane if something goes wrong, software is less good at dealing with edge cases than an experienced test pilot and in order to figure out what the edge cases are in order to programmatically deal with them, you need a human to find out what they even are and figure out how to fix them.
“Faster travel brings the world’s people, cultures, and experiences within reach. Life happens in person, and at Boom we see breaking the time barrier as a moral imperative. XB-1 is the first step in bringing supersonic travel back to the world.”
-- Blake Scholl, Founder and CEO
The life happens in person part currently sounds like a relic from the past. I hope Boom makes it through the travel recession.
They are targeting $5K for round trip tickets between NY and London. It is really just making it faster for the rich to travel for fun or work.
Supposedly it is inherently 3X as expensive as subsonic planes from a cost per seat mile point of view. It is basically a cheaper replacement for the Concorde.
Also it seems that their biggest difficulty is coming up with suitable engines. The engines that they need don't exist and there doesn't seem to be an affordable way to create them.
JAL is one of their planned customers that invested. I make the SFO to Tokyo flight every month. This takes that flight from 11 hours to 3.5. It is not about being rich. At the same cost of a business ticket it means that I do not have to leave on Saturday in SFO to make a Monday meeting (leave Sat. at 3pm and land in Tokyo at 7PM Sunday). I get more time at home with my family.
It’s “business travel” so your company pays for it. The reason you go is for work, not fun. In my case my company pays for premium economy (startup) and I have enough miles and status most times to upgrade. For me that is minimum of 240 hours on a plane a year. Last year I think I spent 500+ hours. It’s work, not some rich person vacation.
I hate points like this. Pretty much all technology starts out for rich people. I mean if you don't have supersonic flight at all its technology will not improve either, neither will the economics of scale.
Air travel itself is already only for the rich, and travel in general is mostly for the rich, if you want to look at it from the poorest in the world.
Elon made this point the best with Tesla, and in 10-20 years the cheapest electric cars will likely be cheaper and better then current cheap gas cars.
I don't believe these 3x cost are actually 'inherent'.
Well that's analogical reasoning at work. Physics would remind you that drag is proportional to velocity squared, so going say 3x faster would encounter 9x more resistance over 1/3rd the time for an energy requirement 3x more than the slow boat.
That's back of the envelope, but it's in the ballpark. Going faster costs more.
They are though. Tesla is a horrible example, electric cars have better fuel economy, so should have a lower TCO for daily users in the long run. Which has always explicitly been Tesla's goal in the long run.
This plane, while awesome, is not a Tesla, it's never going to be as cheap as a commercial flight, and it's certainly not going to make the world a better place.
Fuel cost is far from being the dominating factor in TCO; that would be depreciation. I just ran Edmunds TCO calculator on an Audi A6: 5 year TCO of $70k, with depreciation over 5 years being $35k and fuel only contributing $9k.
Electric cars are nowhere near an affordable means of transportation right now (that would be a Hyundai Accent), so GP point stands true.
How does GP point stand true? Do you think in 20 years an electric car still has a TCO higher than a gasoline car?
In any case, it's what Tesla's ambition is, even if electric cars still have a higher TCO then, it just means Tesla failed, not that it's the same kind of company as Boom is.
That's absurd. An A6 is a much bigger/nicer car than a Model 3. I'd say the A6 is Model S territory, both in size and price. Of course this is complicated by the lower running costs of the S, but the much more spartan interior, which was basic even in 2012.
I've got a Model 3. It's a fantastic car, and as a BMW fan, I'd choose it all day every day over a BMW 3 series. But I'd take the A6 for the same price.
The parent comment said "Electric cars are nowhere near an affordable means of transportation right now". The absolute niceness of an A6 doesn't seem directly relevant to that. Model 3s are expensive to buy for a mid size sedan. I was wondering about the TCO. I found an A5, M3 and Camry TCO comparison (link below): M3 comes out similar to Camry, and way less than A5. I think the M3 is a much more fun car to drive than the Camry. I haven't driven an A5.
Haven’t compared the two up close but the Audi is bigger and probably has a nicer interior because that’s what Audi excels at. I’m inclined to give the rest to the Tesla.
I was not talking about Boom Overture in particular but Super sonic flight. Boom is just the first that could bring it back and innovation can happen from there. Do we really want a world in 100 years we are still flying subsonic?
And if people use it makes the world a better place by some definition. The worst you could say that it used more fuel.
Wait, they don't actually have engines that they can buy that would fit their specs? That seems like a serious issue. There's no way they could fund the design of an engine.
Seems fine-ISH. At least they're selling a different product.
In theory, as an SV DINK, I should be able to afford business class. But every time I try to pull the trigger on the tickets, it just kills me. What, $1400 coach and $7000 business? Times two people? Are you effing kidding me? Those business class seats do NOT take 5 times the space. And they want you to pay double ($2800 or so) for 'premium economy' which is a footrest, "economy plus" legroom (eg, a $100 upgrade), and a bit more shoulder room. Again, it's not 2x the space of a coach seat.
If they're gonna charge 3x as much, and provide a vastly different service, I'm all ears. Even if the seats suck just as much as a coach seat, at least I'm in it for a much shorter time.
It wasn't commercially successful enough to continue operating - partly because it wasn't permitted to fly supersonically over the continental US, through some combination of being too noisy and not being made in the US. Boom is the next iteration that addresses that.
Can it be less noisy? Don't think so. They should climb higher to be less noisy. To climb higher they have to go faster. To go faster they must have blackbird class body and engines. This is a very high ask
Boom's whole value proposition is that they can make it less noisy essentially just by shaping the aircraft right, aided by improved fluid dynamics modelling techniques etc. They reckon they can improve enough to make a difference - or, cynically, improve enough to give an America-first FAA an excuse to approve them.
Yes; we know for a fact that we can make much quieter supersonic aircraft, even for large transport aircraft (existing smaller aircraft of the same period as Concorde were already much quieter, and we've improved on that since). Note however no current proposal for a SST is anywhere near as big as Concorde, which already gives them an inherent advantage.
They kind of were. The development programme was funded by not one but two national governments, seen as Europe's answer to Apollo. The programme didn't even make an operating profit, much less start to pay back development costs. BA claimed to make a small operating profit on it, but only by sharing maintenance costs with AF's loss-making operation; once AF pulled out it wasn't viable even with the prestige it brought them.
I love Concorde but it wasn't really a commercial operation the way you'd usually use the term.
I don’t get the point you are trying to make here. The concord used a certain set of technologies and this aircraft uses another set of technologies with their own challenges. I mean I guess the concord was also a large supersonic passenger plane, but the similarity is largely superficial.
Man I'd be sweating like a pig if I was direct-applying epoxy to a prototype so close to done. I'm used to code where trial and error is de rigueur, I forget sometimes you only get one chance.
I work in aerospace software so I live in between those two realities. Much like software, they'll do testing to make sure everything is bonded. They've also done plenty of modeling to determine what the expected strength is and they have a significant error margin baked in.
...They also don't call them test pilots for nothing...
FTA: ”Boom’s two test pilots were also onsite to verify that all aspects of the wing met their approval.”
I don’t know how well versed these pilots are in manufacturing this kind of stuff, but I would guess that’s mostly psychological. But yes, it’s their lives that are on the line. If this wing we’re to break or fall apart at supersonic speed, I guess they (or one of them, if this is a single-seater) are dead.
Sorry for the late reply... Test pilots by definition are pilots with an engineering background. They're often seasoned aircraft mechanics and/or aerospace engineers.
The biggest change in switching from software to woodworking is that when you cock things up in woodworking, you can't git reset your problems away. The closer I get to done, the more careful I get. Scrapping a part at the beginning sucks, but it's mostly a material cost at that point. As you close in on done, the time dominates the cost, and you get real careful when you have a lot of that in.
Lots of sw engineers dabble in woodworking on their spare time. It tickles a similar engineering nerve, but the lack of "undo" needs a bit of a paradigm shift. You can stare at a piece for quite some time but sooner or later you will have to engage in an irreversible operation.
Being a professional woodworker is not really a viable career option (unless you get lucky). Building kitchens, doing finish carpentry and other related fields of course are, but woodworking is only a relatively small part of that. Very few people can afford the amount of labour that goes into bespoke furniture items.
I keep wondering if planes could benefit from the new materials developed by SpaceX. If they really have a stainless steel that's significantly lighter, it could be a game changer.
As I understand it, they are using 300-series stainless steel instead of carbon composites. Which relates to some novel techniques in manufacturing parts from stainless [1]. But they don't have a lighter stainless steel, which mostly doesn't make much sense because any steel is basically iron in terms of weight--plus or minus depending upon the additives. Some steels are lighter or heavier than others but within a relatively narrow range.
They are supposedly developing a new stainless steel alloy. I've seen indications it will reduce weight on starship. If its stronger, you can use less of it which is effectively lighter. But I haven't seen real info on what they've developed yet.
You are not going to get SS with the strength/weight of carbon fiber. Just no way. SpaceX is using SS for its favorable thermal properties that CF doesn't have.
Not in this case. With SpaceX they also need high (de-entry, Mach heating) and low temperature (cryo fuel & oxygen) resistance but in the case of Boom the surface won’t heat enough to need high temp materials.
That said, I’m not sure their choice of materials is the good one for a startup.
CF prices have come down rapidly in the past 20 years and it's becoming the standard structural material for original airframes. It's more workable and less exotic than it was before. I think most, if not all, aviation startups are using it, like the Icon A5.
> CF prices have come down rapidly in the past 20 years and it's becoming the standard structural material for original airframes.
No and no.
CF can mean anything, but typically you end up with structural members that are heavier than aluminum when all is said and done.
Also, CF is used for sub-subsonic (actually sub-transsonic) skins, which SpaceX found out the hard way.
> It's more workable and less exotic than it was before.
No.
> I think most, if not all, aviation startups are using it, like the Icon A5.
Composites are used for subsonic planes and interiors. And the Icon A5 is a toy.
The one good thing about composite (as in the Diamond Aircraft models) is that it's hail resistant up to a certain diameter and intensity, around 1 inch. That has been helpful with some storms in Florida, for example.
[1] https://boomsupersonic.com/xb-1/build