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XB-1's wings are officially closed out

blog.boomsupersonic.com

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Re: XB-1's wings are officially closed out

#141

Post by raverbashing »

ksec wrote: post #131
gr2020 wrote: post #68

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 - $325…

>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…

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.

Re: XB-1's wings are officially closed out

#142

Post by skykooler »

earthtourist wrote: post #75

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.…

> 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.

I think I prefer a normal airliner design.

Re: XB-1's wings are officially closed out

#143

Post by Reason077 »

TheSpiceIsLife wrote: post #128
ksec wrote: post #127

Earlier quoted context omitted.

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.

The boom in a sonic boom doesn’t come from the engines as such, but rather caused by the object travelling faster than the speed or sound (in air). See https://en.wikipedia.org/wiki/Sonic_boom

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!

Re: XB-1's wings are officially closed out

#144

Post by fcanesin »

Reason077 wrote: post #143
TheSpiceIsLife wrote: post #128

Earlier quoted context omitted.

The boom in a sonic boom doesn’t come from the engines as such, but rather caused by the object travelling faster than the speed or sound (in air). See https://en.wikipedia.org/wiki/Sonic_boom

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.

Re: XB-1's wings are officially closed out

#145

Post by Someone »

AWildC182 wrote: post #48
0xff00ffee wrote: post #35

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.

Re: XB-1's wings are officially closed out

#146

Post by dreamcompiler »

everyone wrote: post #69
yazaddaruvala wrote: post #9

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. [1] https://boomsupersonic.com/xb-1/build

omg that website is freakin' terrible!

Designed to impress rather than to inform. For an engineer looking at the site (me) it does neither.

Re: XB-1's wings are officially closed out

#147

Post by bronson »

AWildC182 wrote: post #41
mauvehaus wrote: post #17

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.

What if a cable snaps or a pulley breaks?

Re: XB-1's wings are officially closed out

#148

Post by fragmede »

gr2020 wrote: post #68

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 - $325…

The data-point for the elephant in the room:

Aérospatiale/BAC Concorde - $169M 150 passengers. Cruising speed: Mach 2

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.

Re: XB-1's wings are officially closed out

#149

Post by MasterScrat »

yazaddaruvala wrote: post #9

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. [1] https://boomsupersonic.com/xb-1/build

Yeah that's like companies who send you a newsletter detailing new features, when you have 0 memories of who they are and what they do.

Take-away: add a one line summary of who you are and what you do at the top of any such communication.

Re: XB-1's wings are officially closed out

#150

Post by xiphias2 »

aetherspawn wrote: post #134
everyone wrote: post #69

Earlier quoted context omitted.

omg that website is freakin' terrible!

I thought the website was really cool. 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.

Probably you're not looking at it from a laptop with touchpad...it's really hard to scroll, also it's really hard to use the keyboard.

I can imagine that with a tablet/mobile phone it's a nice experience.

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