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Airbus unveils 'blended wing body' plane design after secret flight tests (reuters.com)
215 points by hhs 11 days ago | hide | past | web | favorite | 243 comments





BWBs are tempting, but let me state the usual cons mentioned for them.

- More passengers sit farther from the longitudinal axis, and consequently experience larger vertical accelerations from turbulence, as well as normal banking maneuvers.

- More passengers are farther from the windows.

- No great place to put a high bypass turbofan.

I'm hopeful that one eventually gets built though, it'll be interesting how these pan out.


> More passengers are farther from the windows

I’m not sure it’s a big problem: I took a flight in business class of A380, and it was a bit of surreal experience: you are so far from the window, and there are so many partitions, that basically there could have been no window at all and experience would be the same. It was a bit spooky, but turned out fine in practice. On regular flights people actively close shades to use entertainment system, so everyone used not to having windows now.


All other things being equal, I'd prefer a real window. But another thing I'd prefer is being able to look forward instead of to the side.

If they replaced a real window with some kind of system that showed different angles (forward, maybe also downward), that might be a net improvement to me.


Still waiting for the Zeppelin they promised me in the future, with the gigantic picture windows and glass bottomed dance floor.

Even more basic than that, everyone who doesn't have a window seat is not super close to a window. Most 787 overnight flights I've taken darken the windows to the point that no one can see out anyway.

Can we put in skylights?

Any sort of window is a compromise for structure and weight. I think in future we'll see even usual design aircraft to ditch windows.

I certainly would welcome better cameras and better flight info (something that I can connect tho via my own device). Or larger, wider angle windows around bathrooms, bars or other places people go to fight deep vein thrombosis.

That said I've always wondered why business/first in double deckers don't have windscreen. That would be an amazing experience.


>Any sort of window is a compromise for structure and weight

That's fine and we are saying the windows on the sides are now useless so you could simply move them to the ceiling. No compromise. I'm not a huge fan of adding computer screens everywhere and many people probably agree with me. I have been on planes with exterior camera feeds that get piped into the IFE and it's not that great except at takeoff/landing. It's also not the same as natural light.


I like watching the ground ... can we have a glass-bottom plane?

If it's sanity we're trying to preserve, natural light may be more important than a view.

All the luggage is stored below the passenger cabin, though.

make it virtual - like F35 see-through visor does it. Put a monitor + camera outside + "live" stream

There is a business jet line (Falcon 5X/6X) with a single Sky Light. It is basically just a window on the top of the airplane... but definitely cool and unique.

Perhaps the baggage would be placed at the extreme ends, which should reduce the leverage that people moving about would have on the roll axis.

That does exacerbate the window issue, but honestly the last times that I've flown myself and my children seemed to be the only people looking out the windows anyway. Everybody else has a small screen shining in their face for almost the entire flight.


For most intercontinental flights I've been on, at least half the flight the windows are closed to block the sun so people can sleep or watch the screens. They could design a viewing area at the edge and fill the interior (where passengers sit) with natural light from light tubes. Combine that with a few more cameras so you can view the exterior from different angles, and I don't think anyone would complain.

>Combine that with a few more cameras so you can view the exterior from different angles, and I don't think anyone would complain.

While this is fantasy: imagine if you could put on an AR headset and be able to "look through the plane" in any direction. Like that F-35 AR helmet. Maybe allow people to use their screens to also look out around the plane using the same system.


I think there may have been an international gentleman's agreement about not putting external cameras on civil transport aircraft.

It may have been more of a Cold War thing, but I seem to remember running into that in a book at some point that there was a tacit agreement to not do that in the interest of not turning civil transport aircraft into mass produced intelligence gathering platforms, therefore in theory rendering them completely neutral in reference to needing to be taken into account in international sales/intelligence gathering.

I may be completely wrong or misinformed on that though; or the info may have been valid, but hasn't aged well taking into account how capabilities have evolved.


I'm the founder of a startup that's working on precisely this issue; high revisit rate and high predictability of commercial flights + internal window-mounted camera arrays = vastly more data at a fraction of the cost of earth-sensing incumbents (Planet). We're @notasatellite on all the platforms if you're interested.

I remember flying over Cuba a number of years ago and having the captain tell all the passengers to stow their cameras. Evidently it was part of the agreement that allowed the flight path to cross into their airspace.

On the other hand I had no problems getting some good but very distant pictures of Havana a year and a half ago when our cruise ship sailed past.


It's not that fantasy anymore: Emirates' new first-class suites in the 777 [1] have fake windows that display a live feed from the outside.

[1] https://www.theverge.com/2017/12/1/16723152/emirates-first-c...


If I was super wealthy, I'd prefer to fly like that over having my own plane. No matter how much money you have, the pilots are probably better, and it would feel like you were economizing.

Can't reply to salawat, but the Airbus a380 as well as the a340 and others have external cameras you can view in your in-flight entertainment.

At least our Thai Airways A380 only had a singular, front-facing camera at the top of the vertical stabilizer. No other view was possible. But this may depend on the plane's configuration.

On Lufthansa and Emirates A380s, there are 4, but I can't remember exactly the views. One is forward from the vertical stabilizer, one is straight down from the belly of the plane... I want to say another is front landing gear or cockpit?

I figure that would be fun for about 2 minutes.

Definitely would be cool around takeoff and landing IMO. At cruise things tend to look about the same for while though.

That said the last time I flew east to west across the U.S., I was glued to the window as we crossed Utah. Killer views of canyonlands and mountain ranges. I found it was at least as impressive to view them from 35k feet as it was on the ground.


Imagine hitting your head into the person next to you because you can barely move without touching others while travelling via plane.

Also I see no added value of doing this on a plane as opposed to doing the same thing at home with the flight path pre-recorded or even being able to pick from multiple pre-recorded ones.


Superzoom camera on a gimbal would make things quite interesting.

As an adult, my neck doesn't bend in a way that would allow me to look out the window no matter where I sit. I wouldn't have any interest in a simulated view, but a large screen with a camera feed would be great. I am increasingly anxious about flying, but I haven't lost my interest in seeing outside. Seeing nothing but the interior makes it worse.

More than that, at least for me. Maybe half an hour of an eight hour flight? It was on a Finnair A350.

That part where we're crossing Greenland, and you can see glaciers coming down and icebergs in the ocean? Yeah, that was a lot longer than two minutes...

That would be insanely scary. Or maybe the ability to see what's going on outside makes me less afraid of flying.

I noticed this the last time I flew to the East Coast - nearly all the windows were closed. I was somewhat disgusted with the people - why would nearly everyone prefer their windows closed?

> I was somewhat disgusted with the people - why would nearly everyone prefer their windows closed?

as a person who usually gets a window seat, and often closes it, hopefully my response will help you be less disgusted with people: the window seat gives me a wall to lean up against, which stops me from trying to take the arm rest from the center seat, and gives me something to fall asleep against without bothering others. sometimes it's nice to be able to relax without having to get up for others or inconvenience other people.


I’m often annoyed with people that leaves them open when the sun is right there. Blinds me and makes it nearly impossible to watch anything on the screen.

Because I hate the glare and there is nothing to see anyways.

Airlines could do away with Windows for all I care and would probably prefer it.


From my experience flying long-distance - aside landing and take-off, the thunderstorms around the tropics if you're there at night, or when you fly over a new country, there's generally not much to look out at and see unless you're into clouds and the ocean - and even then, unless you have a window seat, you're not seeing much anyway. When I did want to have a gander, it was a good reason to stretch the legs and walk down to the tail of the plane to look out through the door window there.

I think the window issue is already well-solved. Emirates has proven that virtual windows work great.

One more: the classical tube fuselage is much cheaper/easier/more efficient to build, because it consists largely of identical segments. Plus it's much easier to build shortened/lengthened versions of an existing airplane.

It's easier because the current tools of building the planes are not made for this new type of planes. Update the tools and building this new type of plane will be easy too.

Let me quote from the Wikipedia article https://en.wikipedia.org/wiki/Lockheed_Constellation:

> One of the reasons for the elegant appearance of the aircraft was the fuselage shape, a continuously variable profile with no two bulkheads the same shape. This construction was expensive and was replaced by mostly tube-shaped modern airliners. The tube is more resistant to pressurization changes and cheaper to build.

With blended wing bodies, you would again need a continuously variable profile for the whole fuselage (rather than only the wing, as in modern "tube-and-wing" planes). To build a larger or smaller variant, you would have to redesign the whole fuselage, rather than just adding/removing a few tube segments. So, even with updated tools, there will still be a lot of challenges...


In todays world of most high value things being CNC machined rather than made from hand crafted moulds and templates, every part being different is less of a concern. Just download the set of designs to the machine, do a test run of the smallest and largest part, and then hit 'start' and come back in the morning.

This is so, so not the case! If anything it's the opposite.

First of all, nobody is CNC machining airplanes from billet. They're sheet metal structures. But that aside...

For handmade structures with little tooling, the difference is less because it takes only a bit more training and about the same amount of time to make a bunch of unique parts as to make a bunch of identical parts. The economies of scale are there, but less so.

But even for CNC parts, extra shapes means extra CNC programming time (expensive but amortizes over the number of pieces made, so n unique parts costs n times as much to setup and amortizes n times less). It means more inspection gauges. More tooling. Significantly more inventory costs.

Design a machine from a single modular piece, and all else equal it will be much cheaper than one made from a bunch of unique parts.


Modern aircraft, as in 787 and a350 are mostly carbon composite structures by now. I image that would be even more the case for a blended wing body Design

You're not machining large surfaces like wings, windmill blades and the like, not just because it's hard to make machine tools that size but because the structure and performance of the materials depend on not being machined.

When you machine an amorphous or crystalline material like a metal alloy you aren't always simply removing material, but can be putting a specific finish on the surface for mechanical reasons. Sometimes you want to cast again for performance (or cost) reasons because machining can't get you what you want.

When you build a shape from a composite material such as fibreglass in epoxy you want the longitudinal fibres to run long distances to distribute the stresses. Machining it would defeat the purpose. They are cast.

I like these blended wing designs; I'm just pointing out that your argument is not applicable to this application.


They are made from composites. The moulds are machined.

Airliner structures are very conservative. They still use a lot of fasteners, lowering manufacturing and structural efficiency.

There is a lot of room to improve. There is a huge space for innovation in composites. It just takes a lot of time and money to ensure the more modern methods are also durable and safe.


Also in today's world it is cheaper for one machine to produce 1.000 identical parts than for the same machine produce 10 times 100 different parts. You need stock of each, tests of each.

Imagine how efficient car maintenance would be of only we'd use one standardized car. You can have the larger model, but all components are the same, every garage has them...


Like Tesla is doing with one engine for all cars and a mono frame pressed out of a metal sheet. Cybertruck deliverable in every color you like as long as it's metal. I have read somewhere the complexity in production lines are similar as the big O notation. Henry Ford would be proud of Elon.

Most car manufacturers are massively reducing complexity. Toyota's Next Generation Architecture is reducing total manufacturing costs by 20% by simplifying their entire platform of vehicles into a common set of types and using similar hardware wherever possible.

3D printing.

Yeah, a passenger aircraft is somewhat more complex in manufacture than a MacBook Pro.

I imagine even larger gantry variant of this carbon fiber loom:

https://www.youtube.com/watch?v=j19na8LMBnE


A tube fuselage is also easier to build offsite. Boeing still carts 737 fuselages back and forth across Seattle on the railways.

Have you seen how Boeing was building (well, how Mitsubishi was building, in point if fact) carbon fiber wings? They were doing it with carbon fiber ribbons as a single piece.

I don’t know if that scales up to the size of a blended body, though.


Not just "across Seattle". From Wichita to Seattle.

From what I can tell of the passenger airline business over the last few decades, lots of people will say that they would never fly in such an aircraft because of those things, and it wouldn't be true.

Lower cost - they'll fly. Over and over and over, lower cost? They'll fly.

Here's Forbes on it back in 2015; https://www.forbes.com/sites/airchive/2015/01/14/actually-ai... , and here's someone else on it in 2016; https://www.businessinsider.com.au/scandinavian-airline-sas-... , and someone else in 2017 https://www.marketwatch.com/story/heres-what-us-airline-pass...

Price. Price. Price. That's what passengers show they care about through their actions. They like to pretend, we all like to pretend, but the evidence is clear.


It's to the consumer's advantage to tell his buddy about how terrible such-and-such-an-airline's new cuts to foot room are and how he wouldn't fly and neither should anyone else. That could possibly lead to better policies. It's not to his advantage to skip flying or to by a more expensive ticket. People are acting according to their best interests, nothing to see here.

I disagree.

If the consumer convinces everyone else not to fly on those cheap flights, the cheap flights discontinue and the consumer is left paying more. How's that to the consumer's advantage?


I disagree that people will for sure choose price over uncomfortable aircrafts. The most clear thing to look at is turboprops vs regional jet aircraft.

Turboprops cost less to buy and burn less fuel(on shorter routes) and take roughly the same amount of time for hourlong trips. But yet, at least in the US, turboprops have been almost completely replaced by regional jets.

This is because passengers prefer the small jet experience to the small turboprop experience, even though the turboprop is cheaper.


I have heard the alternative conclusion that the expense and reduced inter-changeability of airframes in a mixed fleet of turboprops AND jets, outweighs the costs of just jets, and furthermore the US domestic market has seen a reduction in demand for the short flights that turboprops excel at.

Put another way, the jets are cheaper, even though they individually cost more and burn more fuel. That the turboprops have been phased out of larger airlines that both run long distance flights and would benefit most from the economics of just jets in their fleet, while turboprops are still in use at smaller airlines who would not benefit as much from a single airframe fleet and serve a higher proportion of short distance routes, does seem suggestive.


Interesting theory, and I'm no expert, but it doesn't feel correct to me. Of course United flies only jets, but it has a variety of regional partner airlines that also fly only regional jets.

In a slightly similar way, FedEx operates only jets but for small cargo routes seems to operate only propeller planes (along with its large FedEx feeder partner feelts)[1]. This could be for a variety of reasons, but it seems most logical (to me) to assume that props are more economical and of course cargo doesn't care about comfort.

[1] https://en.wikipedia.org/wiki/FedEx_Express#Fleet


Cruise ships handle plenty of non-window "accommodation": https://www.royalcaribbean.com/blog/an-inside-room-with-a-vi...

I've been on a lot of cruises. Aside from sleeping, I'm pretty much never in my cabin. Doesn't really make for a good comparison to a flight.

For a certain price, you’ll find someone to do it

I've never been on one; to some one who has, how do you avoid going nuts or getting depressed after a few days?

I deployed on a sub five times in four years, so I'm maybe not the best one to give an example. For us, we got used to the 'no outside' within a day or so as there is always so much else to do.

Long term, you make friends, come up with portable hobbies, and just dig in to the job for a while.


Consume as much food and booze as possible to drown your depression caused by being crammed on a disease-ridden ship with 3,000 strangers.

I think the airlines will find a way to turn these problems into advantages.

- Passengers won't have "normal" seats far from the plane's central axis. The distal axis seats will contain steward seating, bathrooms, additional storage, and maybe even a small lounge.

- Windows on planes are dirty and small. You're also dealing with more noise and vibration being closer to the frame and engines.

- I don't know enough about turbofans, where can I learn more about the bypass limitations?


- Placing bathrooms and lounges where turbulence is guaranteed to be highest strikes me as a potentially poor idea.

- Airliner passenger windows have been getting bigger. https://i.imgur.com/ISWgvZF.jpg


The 1925 Ford Trimotor[1] had big beautiful picture frame windows. A silly comparison but if you've ever flown in one you'll know what I mean when I say they had a luxurious view of air travel.

[1]: https://en.wikipedia.org/wiki/Ford_Trimotor#/media/File:NC84...


I had the privilege to take a flight on one a few years ago; aside from the expected difference in engine noise (which was actually way more fun as an aviation buff) it was rather comfy for a seventy year old design. And yes, awesome views from the row behind the cockpit.

Windows have not been getting bigger as a rule. Boeing did make larger windows but Airbus didn’t. The A350 has small windows.

Window size is also not the main factor that matters. For instance I would take an A350 over an 787 any day (also because of the terrible tint windows) due to cabin layout and size.


Why not just more seats? If the cost of the flight is lower, people will buy it. They will, over and over. They kick and scream and say "this, this, THIS is the line I finally won't cross" and then they buy a cheap ticket.

Here's Forbes on it back in 2015; https://www.forbes.com/sites/airchive/2015/01/14/actually-ai... , and here's someone else on it in 2016; https://www.businessinsider.com.au/scandinavian-airline-sas-... , and someone else in 2017 https://www.marketwatch.com/story/heres-what-us-airline-pass...

Price. Price. Price. That's what passengers care about. Same story, over and over.


I'm very much in this camp. Two weeks ago, my 6 member family took a flight on Frontier, one of the discount airlines, from Philadelphia to South Florida. The seats didn't even recline! But don't take that as a complaint, the fact that we paid $611.79 for 6 round trip tickets (and 2 checked bags) makes up for the slightly less comfortable trip and no pretzels.

Fares like that make flying possible for so many more people now. If we had to pay $200 or even $300/ticket (instead of $100) it would have made the trip unaffordable.


The seats didn't even recline!

I'd actually pay a little more for seating that didn't recline (or rather, for the seat in front of me not to recline, but more than happy for that to be the case on all the seats). Genuinely would. Not a lot, but a little.


Second emergency exit row on Ryanair (AFAIK they fly 737's exclusively) costs about $30. It reclines but seat in front doesn't...

The line for me is United's "basic economy". I'm pretty sure I'd have difficulty fitting in the seat because they're so small; I'm skinny enough, but have long legs. There's a line between "nice-to-have"s (extra room, early boarding, etc.) and things that make passengers plain uncomfortable, and that's it. This is true for a good number of others I know, too.

Is that the line? How much of a discount would you need to cross it? 50%? 20%?

If you wouldn't cross it, how many people are there poorer than you who almost, almost fly? There are a LOT of them. A LOT.


The article shortly addresses these points:

... One unresolved question is whether such a plane would have windows or use video screens to give passengers a sense of their surroundings.

Another issue that has dogged such experiments in the past is how to handle sensations of movement.

Because passengers would be sitting further out from the center of the aircraft, compared to the classic ‘tube and wings’ model, they would move further when the aircraft turns. Rival Boeing has put more weight on a potential cargo role.


It would be neat to put windows on the floor. You’re most interested in looking down anyway.

And otherwise you could have a cool hang out / lounge with nice pa Aramaic windows and everyone could have turns sightseeing.


That's not a very good idea. Most people are terrified of glass floors in other scenarios, like balconies for example, especially combined with some altitude. It may be just as safe as "normal" windows but I doubt most people would be comfortable with it. I'm not even sure I would be and I have no more fear of flying than most people. I'm not sure it's suitable for other reasons as well, such as hull integrity (but I'm not an engineer), or actually getting sunlight into the cabin. I'm fairly sure most people want to watch sunsets and sunrises, not clouds or how insanely high up you're sitting.

> It would be neat to put windows on the floor. You’re most interested in looking down anyway.

I don't think so. Looking down isn't what people look out the windows at, it's the horizon. Looking straight down would be generally frightening, sickening, to many people... whereas the horizon is steady and calming.

But either way, once you're above the clouds, windows are OK but kinda useless. View doesn't change much up there, or at night!


> It would be neat to put windows on the floor.

Depends on if they put cargo down below or not. Makes sense they would so they can easily on/off-load it.


project the open sky on the ceiling

Don’t forget mrfusions law. “Any screen will eventually show ads”

>More passengers [...] experience larger vertical accelerations

Economy-minus section?


To be honest, air travel used to be very noisy and expensive, sometimes with fumes events, let alone smokers. Despite the legroom, I’m pretty sure it is more comfortable now.

Please, that's an Adventurer seat and costs more than economy.

> More passengers are farther from the windows

Why is that a con? Seems to me most people don't like window seats & want aisle seats.


Well, you also end up with longer rows - and so potentially more middle of row seats which are less desirable.

Or you create corridors? Most 10 wide have a 3-4-3 already and if you have more horizontal space 3-3-3-3 might be an option with the same amount of middle seats and two extra seats.

- No great place to put a high bypass turbofan.

This especially. USSR Tu-154 with a 3rd engine in this spot was very affected by aerodynamic shadow from a airplane body at certain angles.


I wonder about egress during an emergency as well.

I think I'd like windows in the floor so I can see what we're flying over. But I doubt that will be very popular.

On any current airliner a window in the cabin floor would only allow you to stare at your luggage. That arrangement seems to efficient to change just for the sake of a bit of a view.

Airlines don't care about our comfort. They would ship us in intermodal Connex boxes if they could.

I would definitely try "BA Baracus" mode for intercontinental flights if it were available and safe.

I pity the fool...

People don’t care about comfort, airlines just sell what people pay for.

Exactly this. There is plenty of comfort available in air travel if you are willing to pay for it.

In a way windows are more of a psychological problem I think. They are already quite small and not that reachable for most passengers, but closing an option is tough.

Would it be possible to have at least roof windows for natural light or then it's not worth the bother?


Less windows = less chance an aircraft would depressurize. An array of small roof windows could be a solution.

https://edition.cnn.com/travel/gallery/stephen-chang-imagina...


> as well as normal banking maneuvers

Aren't these maneuvers done such that the local acceleration for all the passengers remains pointing straight toward the bottom of the plane, so that if they close their eyes they don't feel like they are tipping at all? Why can't this continue to work for BWB?

I also don't really understand the turbulence issue. Do planes typically roll during turbulence? My experience has been mostly vertical vibrations.


That's once you set the bank angle and are turning. But in order to initiate the bank you need to apply a torque (via ailerons). If you sit at distance d from the axis you'll experience an acceleration due to this torque changing the angular velocity (four times per turb: once when the banking is initiated and the second time in the opposite direction when the desired bank angle is reached; then the same thing reversed when existing from the turn). An increased distance d exacerbates the effect (think of a lever).

The trajectory is the second integral of the acceleration, so if the local acceleration were pointing exactly straight down at all times, you'd have to be moving along a vertical line.

That's the first thing that went through my mind when I saw that picture. "No windows--I'm not flying on that."

Wasn't the main issue that flying wings have a very narrow Center of Gravity range? I thought the main reason that airliners have such a large trimmable horizontal stabiliser is to configure for varying CofG.

Yes, but it is harder to get a long ways from the center of gravity on a flying wing.

This will not slash carbon emissions by 20%. Blended wing body will make flying cheaper, and increase the number of flyers.

Global flying demand has been increasing[0] year-on-year and is estimated to continue increasing[1] into the foreseeable future, partly due to flying subsidies provided by many countries[2] to encourage tourism, etc. If you are alluding to a problem of people flying too often, I would work towards eliminating these subsidies first.

[0]: https://www.statista.com/statistics/193533/growth-of-global-...

[1]: https://www.iata.org/contentassets/d4b60cffceeb4213bb5993d5f...

[2]: https://www.researchgate.net/publication/318691221_Subsidies...


.... which inevitably turns flying / vacationing far abroad back into something exclusively for upper class people, which is easy to advocate for when you work in the tech salary bubble.

If we're gonna slash subsidies and introduce carbon tax on flights, it needs to hit corporate and expensive tickets as hard as possible whilst sheltering cheaper tickets as much as possible.

There's so many things HN proposes should be taxed / excised extra: cars, flights, gas, soda, alcohol, meat, rare metals in devices, batteries, electricity consumption etc etc.

They aren't bad ideas (hell, I agree fully with the sentiment of most of said ideas) but it's so easy to be blind to the fact that you'd basically be turning daily life into a two caste system where only the rich are allowed vices.


Hmm - if you have super rich you have inequality be definition - don't know why you are focusing on flying - what about super yachts or effective immunity to prosecution?

If you don't like inequality then there are other ways to deal with that - rather than using it as an excuse to keep flying.

I do however agree that a frequent flyer tax would be a good start, though be aware that a lot of airline routes are effectively funded by business class seats, so you might find flight frequencies dropping - but that's the point right?


> .... which inevitably turns flying / vacationing far abroad back into something exclusively for upper class people

Is it not already primarily upper-class people vacationing far abroad?


> Is it not already primarily upper-class people vacationing far abroad?

I don’t think of someone who makes $400k+ a year working as a software developer as necessarily upper class. In my view, upper class means someone who is financially independent and can afford to not work for money for a year or longer without a change of lifestyle.


Only on HN will you find someone seriously arguing that a salary of over 400K USD a year does not make you upper class. Sure, you can't afford to stop working for the rest of your life, but with a salary like that you're only a few years away from being able to if you wanted.

No amount of salary makes you upper class when the class boundary is defined by having passive income sufficient to meet all expenses.

A salary of 2x expenses will put you in the upper class within 22 years (with average market returns), and passive income will fully replace the salary within another 8 years, but until then, that's still middle class.

Basically, if you can afford to invest 1/6 or more of your income, you can make it to upper class within your lifetime, and still have time left to enjoy it.


I make $20k-$30k/year, and though I don't fly very often, I do enjoy traveling and seeing new places. I have flown to quite a number of destinations and I'm definitely not upper class. I would fly still more if ticket prices continue coming down, though I'll want window seats.

> Only on HN will you find someone seriously arguing that a salary of over 400K USD a year does not make you upper class. Sure, you can't afford to stop working for the rest of your life, but with a salary like that you're only a few years away from being able to if you wanted.

Sorry but I think we need to be real. We are not the middle class. We are poor working class people. Most of the 10% is squarely the middle class. I'd imagine a big chunk of the 1% is middle class because one medical crisis could likely bankrupt them. Look at the wealth distribution graph.

https://upload.wikimedia.org/wikipedia/commons/5/5d/Wealth_d...


400k a year is not "poor working class" by any definition of the word. The median salary in America is 45,000. "Poor working class" is significantly below that. 400k is upper middle class, and if you've not managed to save up for a rainy day on those kinds of wages, it really is your own fault. Actually poor people manage it.

People from the Bay Area really need to get out more. Source: I come from the actual poor working class.


I meant to say those making 400k are the middle class. I don't make anywhere near that much.

400k is not "middle class" -it's upper (upper upper) middles, and yes, there is a huge difference. It's literally top 1% of income!

https://www.investopedia.com/financial-edge/0912/which-incom...


The existence of the mega-rich doesn't make the "merely wealthy" middle-class.

Here's a bit from the Washington Post in 2017 talking about the difficulty of defining what is "middle class" in the modern era. They arrive at an umbrella of $35k-$122k. https://www.washingtonpost.com/news/wonk/wp/2017/10/25/is-10...


I'm all for fighting inequalities but the way you frame this argument is frankly obscene to me. The average salary in the US is about $60k/year. Worldwide average is hard to establish precisely due to the many factors to consider but it must be around $10k to $20k.

Saying that you're part of "poor working class people" when you earn in a year what a significant number of your compatriots wouldn't earn in a decade is a ridiculous thing to say.

I commend you for being outraged at the insane inequalities in our civilization and I largely share your concerns but you really need to work on framing that better IMO.


A well-paid peasant is still a peasant.

Remember when the big tech co's were conspiring together against their own employees?

"Apple and Google's wage-fixing cartel involved dozens more companies, over one million employees"

https://pando.com/2014/03/22/revealed-apple-and-googles-wage...

You're just buying into "The Man"'s propaganda to keep the working class divided, yo.

(It reminds me of a joke from Futurama. Leela gets a bunch of valuable stock and says, "Wow! I suddenly have an opinion about the capital gains tax!")


You need to spent a year of two being really middle class in the US.

I wasn't completely serious just then, eh?

Anyway, I am "really middle class".

Heck, I was homeless for about four or five years.

When poor serfs complain about less-poor serfs I like to point out that it's the lords they should be grumbling about, if anyone.


> In my view, upper class means someone who is financially independent and can afford to not work for money for a year or longer without a change of lifestyle.

Someone making $400k/year should easily accrue the savings to do that.

If they're not after a year, they need to re-evaluate spending habits.


I guess the question is: if it got more expensive, would that mainly result in people no longer being able to vacation abroad, or just not doing it because they don't think it's worth the money, even though they can afford it?

If it's primarily $400k+ software developers who currently vacation abroad, then that wouldn't be that strong of an argument against removing the tax incentives.


I know it has some pretty poor "optics" but I like what I've heard of carbon pricing that Canada. From what I've heard, there is a decent allowance for every household and it starts to cost money when you go over the allowance. The allowances are set so "most households will get more back than they pay as a result of pollution pricing". https://upload.wikimedia.org/wikipedia/commons/thumb/4/42/Ex... https://en.wikipedia.org/wiki/Carbon_pricing_in_Canada

I am not opposed to a more progressive income tax. In fact, I firmly support higher income taxes on everyone. I could never run for political office in the US because how will I ever walk up to a constituent and say "I want to drastically increase your taxes?" and at the same time walk up to public sector employees and say, "I want to take away your benefits".

Yes, we need to address climate change. However, I think we also need to encourage travel so we can facilitate movement of people and ideas across the world. Not everyone who travels will change the world but I'm sure it can't hurt.


> There's so many things HN proposes should be taxed

I think you got my statement backward. I was advocating for the removal of taxes, since AFAIK subsidies generally utilize tax money. Maybe as you suggest, "hit corporate and expensive tickets hard" to subsidize the flying for the poor (economy) classes (which I'm assuming already happens).


> whilst sheltering cheaper tickets as much as possible.

I'm sorry, why? I don't see being able to travel across the world at high environmental cost to be some god given right. It's not sustainable, especially as use of long-distance travel continues to grow with no end in sight. Make it expensive for everybody, instead of subsidizing it for whatever group you have a bias for.


I still can't wrap my head around the prominence of this idea that the only way to solve our problems as a species is to live worse lives and to be more disconnected from others.

Whether "it" is international travel, point-to-point personal transportation, or whatever, make it sustainable for everybody, instead of criticizing it for whatever group you have a bias against.


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We've banned this account for violating the site guidelines and ignoring our request to stop.

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There is talk of a "Frequent Flier" tax that could be used to address this.

Currently 70% of the flights are made by 15% of the population (1). If you start adding increasing taxes on each additional flight you take, it would rapidly curtail a lot of the travel I'd expect.

I am sure a lot of us in Europe (and perhaps USA? Not sure if it is as prevalent) in the past have been guilty of taking a "weekend break" somewhere that is a 1 or 2 hr flight away where the tickets usually cost something like £30-40 return on Easyjet or Ryanair (and often cheaper than a taxi to get to the airport!)

E.g. after 2 flights a year, start adding £50 per flight (so 3rd is +£50, 4th +£100, 5th +£150 etc etc). Suddenly your £30 return flight from London to Lisbon/Rome/Dublin/Barcelona/Berlin etc is no longer so absurdly cheap. Put all the proceeds from the tax into decarbonisation and fast intercity rail.

That would soon make people (myself included) think twice about taking "frivolous" city-breaks every month or so where you fly out after work on a Friday and come home again Sunday night ready to be back at your desk on Monday morning.

1 - https://fullfact.org/economy/do-15-people-take-70-flights/


The problem I always see with using taxation to solve problems (to prevent too many people from doing X), is that you're filtering by socioeconomic status. You're making it so that only the richer people can do it, and the poorer people are screwed once again. It's a simple fix from an institutional point of view, and it might "solve" the problem, but it just feels wrong to me. Not that I have a better solution though...

Welcome to the real world. Besides, how many poor people are flying multiple times per year anyway? I don't have the numbers, but I would bet that this tax would be paid overwhelmingly by businesses on behalf of their employees who travel for work.

And that tax would be absorbed unnoticed in the businesses' expense again right next to the reciepts for over-priced steak dinners and strip clubs. The whole reason airlines can get away with charging so much for business class is because businesses don't generally give a shit if their sales personal are charging them for in-flight champagne when they go to close a billion dollar contract. The truth is that you'll have to be more strategic than randomly throwing a tax at the problem if you want to change the behavior of entities who already dump hundreds of thousands on maintaing a private jet fleet so that a C-level doesn't have to wait in line at security.

You could have a revenue-neutral carbon tax, where each person gets a share of the tax proceeds, and then lower income people get paid on net when they don't consume carbon

In the US, we would probably drive our own cars anywhere within a 250 km (150 mi) radius, which costs about $170 in fuel and vehicle maintenance, and takes about 2 hours each way.

Tax flying in the EU, and people will likely take more trains. Try it in the US, and you're just pushing people back into their cars.


For a trip of 150 miles, does flying have a lower carbon footprint than driving? (For that matter, for any distance, same question.)

Airliner aircraft burn more fuel closer to the ground, at takeoff and landing, and less fuel at cruising altitude, where the air resistance is less. On shorter trips, the proportion of the trip spent at lower altitudes is greater. Some flights might not reach optimal cruising altitude at all.

One can adjust the flight profile for maximum fuel efficiency, but this tends to be uncomfortable for the passengers and crew, and it takes longer to reach the destination. Most US passenger airlines don't do that, but military and cargo carriers will.

That aside, some portion of the fuel is spent continuously keeping the weight of the aircraft aloft, and with ground vehicles, the equivalent expenditure is the rolling resistance of the tires. Furthermore, an airliner plane tends to carry all the fuel it needs for the entire flight on takeoff, which translates to additional weight, whereas the ground vehicle can refuel enroute at a truck stop or gas station. Some aircraft can refuel in flight, but another plane has to carry it up there and maneuver it into place. A train on electrified rails need not carry any fuel at all.

So to some extent, it depends on the ground vehicle and the aircraft. In a contest between an ultralight or powered paraglider and a heavy pickup truck towing an RV trailer up in the Rocky Mountains, the flyer might have a lower footprint. But for a trip over flat ground, such as Chicago to Indianapolis or Cincinnati to Cleveland, in a medium-sized hybrid ICE+battery sedan, driving at or below the posted speed limits on US Interstate or Autobahn-like restricted access divided highways, I think the car will win against anything other than a solar-powered lighter-than-air craft.

I haven't done the bar napkin math, so I could be wrong.


It's pretty obvious that the measure used is carbon emissions per passenger mile, not worldwide carbon emissions of aviation.

You're right, but talking about individual passenger emissions doesn't make much sense since the issue of carbon emissions is a global one.

Then the measure is wrong.

It depends on legislation.

AFAIU currently kerosene is very lightly taxed, if at all. If there is taxation of fuel or fuel-based payments for airlines, it will be reflected on ticket prices more than currently.

So the airlines can claw some of that back by introducing more efficient planes. But they will be expensive to develop and build, which is again reflected in ticket prices.


Exactly, this is called the Jevons paradox.

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


* emissions per person-kilometer of flying, of course. I thought this was implied. It works this way with any optimization of any transport method.

Great, you're right; screw this design, and maybe let's even regulate flying to be more inefficient per mile so as to reduce total flying.

More subtly though, yes you are right; we need to dedicate some money to carbon offsets and not pass all of the savings to passengers.


How much of a plane ticket is the fuel cost? For example, New York to Paris.

So here are the numbers for New York to Paris. I used a 737 Max 7 for this since the max range is right about the same distance so the math is easy and the 737 Max is a fairly efficient plane but an A321 neo would be similar. Albeit a 737 or A321 neo are not planes that you would fly New York to Paris in.

So it is looking like jet fuel is around $2 a gallon for airlines right now.[1] A 737 Max takes a total of 6,820 gallons.[2] Since the flight from New York to Paris would be almost the max range we can assume all of it would be burned to transport the 172 passengers.

So ($2 * 6820 Gallons) / 172 People = $79 per person in fuel.

[1] https://www.statista.com/statistics/197689/us-airline-fuel-c...

[2] https://en.wikipedia.org/wiki/Boeing_737_MAX


Last time I bought a Ryanair ticket I was offered to purchase a co2 emission offset.

The price was less than 1 euro.

Telling me that there better ways to lower co2 emissions than not flying. (Or creating new airplanes.)


I'm not sure what your point is, but I wouldn't trust Ryanair's suggestion of how much to pay to offset their CO2 emissions, or that they'd use that fee effectively.

It tells you something about how expensive it would be to have someone else save the CO2 you have emitted by flying a plane.

But you are right. The price going to purchase the CO2 offset is probably less than what I would be paying.


Given that:

a) Flying is basically the only practical option for long-distance travel (edit: by which I mean humans travelling to be at a destination, not cargo/goods).

b) Travel is a hugely important good for society (debatable, but consider: experience of diverse cultures, being able to visit friends / have relationships, generation of economic value by skill sharing / conferences / etc).

I would argue that anything that increases the amount people are flying / lowers barriers to travel is a good thing.

Obviously if we can lower carbon emissions from airlines then we should, but I'd much rather curtail ANY other industry that produces huge amounts of emissions before trying to cut down on human travel.


It is the most practical long-distance option. But we should be able to give up things that are bad, even if they're practical (like asbestos – an amazing material, but it causes cancer to those who have to work with it).

Traveling is nice. I'd argue that most flying done nowadays does not increase cultural understanding. Hitchhiking or slow and uncomfortable means of transportation do increase cultural understanding, because they force people to share something. Modern traveling technologies offer a chance to travel half the globe while staying in a safe bubble. By the way here's an interesting phenomenon that you can notice when people talk about their travels. Stories always revolve around technical issues. Flight was cancelled, they had to take a cramped bus through the mountain, something was broken in the hotel, they got delayed when crossing a border. Traveling is often a game of moving around in unusual and adverse circumstances, and somehow making it work in the end.

Climate change is currently hurting economies, and the trend is worsening. Something that contributes to climate change is bad for the economy.

Having friends far from home is a bad choice. I've done it myself and it does have something attractive. But it makes life more difficult and these friends won't be there when you need them, simply because it's not practical. Of course it might sound great to say that someone flew thousands of kilometers to visit you. It sounds great because it's a huge waste, like showering a loved one with flowers.


Even if we go by your choice of total emission instead of a normalized one, it will then slash emissions by what, 15%?

Good example of second order thinking

fuel is a very small percentage of a ticket price. Depending on route, more than half goes to airport taxes and then crew services etc.

That’s ok too.

So Jevons paradox is garbage, it's neither true nor is there evidence it would be applicable here even if it was true.

Moving on.... you're playing with words, they are talking about specific flights.

At to a global level it might be a 15% reduction or maybe 18% for these specific flight routes. But they make no claim to know that figure. It's hard to know. They just are presenting facts.

And for the 2% or 5% or whatever difference to the 20%, that's people making flights that couldn't before. That's people exploring the world. That has amazing value as well. It's not just 'less than 20%'


So my understanding of Jevon's Paradox is that when efficiency increases so price decreases. When price goes down then usage goes up.

What's the argument that that's garbage - or is my description not a good one?


It's impossible to tell from that argument whether total usage of the resource will be higher or lower than in the alternative universe where efficiency never increased. Usage will go up, but it might not go up enough to completely offset the efficiency gains.

> So my understanding of Jevon's Paradox is that when efficiency increases so price decreases. When price goes down then usage goes up.

No, it's the usage of the resource made efficient will be more than before, not the product.

The reason people believe it, other than annoying blogs saying it's true, is we can see as efficiencies increase price goes down and we will use the product more, so it mind hacks people about the resource

But it's really hard to ever intuitively see if the resource gets used more.

I think the original idea seems legit, it's just never been reproduced that I've ever seen. I've never seen a legit example of Jevon's Paradox outside of the original idea.


This kind of design could be extremely important as a way to make enough room on board for hydrogen fuel tankage.

The mass/energy ratio of hydrogen makes it an extremely attractive aviation fuel. Its lower volumetric density has made it impractical with current designs, for most potential uses. Lifting bodies enable an elegant resolution to that problem. After some time it may be considered uneconomical to fly the old submarines-with-wings airframes.


That’s actually a great point, if you can get a lot of extra volume “free“ with a BWB design then it could make hydrogen a more viable airline fuel.

If I have extra volume in the airframe, and I'm using it for fuel tanks, why wouldn't I use it for conventional aviation fuel and extend the range of my plane? I can use existing infrastructure, not have to worry about cryogenics, not have to worry about high pressure fluids...

We know how to use aviation fuels safely now. Although hydrogen is interesting as a potential fuel, I don't anticipate its use in the near future.


Existing aircraft have plenty of range already, and would not be able to (usefully) carry much more fuel anyway.

Existing infrastructure is much less important for long-haul aircraft. Facilities at just a half-dozen key airports -- say LA, NY, Hong Kong, Paris, Mumbai, Tokyo -- would suffice to bootstrap it. (Compare to, e.g., trucking, needing hundreds of stations.)

Aerogel-insulated tankage would make carrying liquid H2 easy and safe.

The value proposition is that a huge fraction of the expense of operating a long-haul carrier is hoisting the heavy fuel up to 40,000 ft. and keeping it up there. Enough H2 to get the same range weighs a third as much; the difference can be used for payload.

H2 can be produced direct from wind or solar when it's windy or sunny (respectively), and stores up power for peak demand, as well as for aviation fuel, so there are huge synergies in developing H2 production for multiple uses.

There is quite enough experience handling LH2 for rocketry. Probably carrying some LOX or H2O2, too, would enable flying at 60-80000 ft, for even more efficiency.

Not venting CO2 will matter when that is taxed, as it should be already.


The point would be to reduce the carbon footprint, for which currently there is no practical technology for aviation (which can make more than a small incremental reduction).

If you are just considering a companies bottom line, obviously they are just going to do what would make them the most money.


Liquid hydrogen actually has the best energy density by unit of mass than any other fuel (combustible fuel, nuclear is on a whole different level). If lightweight cryogenic storage is developed, then hydrogen powered plans could be a viable option.

Because it can't carry enough weight to fill tanks that big with jet fuel? Hydrogen's light, though very bulky.

Because the industry is looking to create a zero-emission alternative.

The window issue is a red herring -- if leaving them out saves money people will continue to buy the cheaper tickets. The airlines have proven that over the past couple of decades.

As for vertical motion, perhaps the same applies: first class will be in the middle; economy passengers farther out, and fuel, baggage and crew areas will be farthest from the centre.


If you want low carbon transport then https://www.maritime-executive.com/media/images/article/Phot... is very hard to beat.

Over a hundreds times better than air....

The problem the airlines face is they are effectively massively subsidize with tax cuts on fuels and duty free status at airports etc plus their free environmental dumping of huge amounts of C02.

Air travel and freight is, by and large, is a luxury. Yet people are willing to let the world burn rather than give it up. I'm sure someone will tell me there is some scientific name for such illogical behavior.


Sending air mail is a luxury now?

Global aviation produces something like 2% of global co2 emissions

As for shipping, it uses 4.5% of global co2 emissions. Source https://www.theguardian.com/environment/2008/feb/13/climatec...

What's more, here is what @BurnGpuBurn [1] pointed out before:

"Shipping also very often uses the dirtiest of fuels and is therefore much more polluting than airliners which burn quite high quality refined fuels. That's why, to get around recent laws limiting sulfur emissions, large container boats now first "scrub" their exhaust gasses with sea water, so all sulfur will now nicely pollute and acidify our oceans. [0] No emissions though, because emissions bad."

[0] http://www.imo.org/en/MediaCentre/HotTopics/Pages/Sulphur-20...

[1] https://news.ycombinator.com/item?id=21979576


So similar emissions, but only one of them transports 90% of the worlds goods, raw materials and waste.

> Sending air mail is a luxury now?

Yes - either wait a bit longer if you need to send a physical thing - or if it's just a message then do it electronically.

Yes - perhaps an email isn't as 'nice' as a real letter, but isn't that the definition of luxury?


> So similar emissions

Did you read my 2nd point? The emissions are not similar. Please also follow up on the source I've provided.


Not saying boats are perfect or that every company that runs them are angels! But you have a lot of head-room if you start off 100x better kg per kg.

Because boats are not perfect doesn't change the original point:

A 20% saving on emissions for aircraft and talk of 'having more space for cargo' is missing the big picture - air travel is a massively subsidized luxury where the speed of travel comes at a massive energy cost.


This is a bit of an oversimplification though. The duration of moving people by ship means that people need to be given food and water. People also aren't going to be spending the entirety of a weeks long voyage in a seat - they'll need beds and recreation facilities to stay sane. You're also less likely to find large numbers of people who all want to depart and arrive at the same time, so filling a large ship to capacity is more difficult and the ship will be running partially empty much of the time. All these things lead to lower net efficiency.

The reality is, people aren't going to give up air travel. The best bet to make air travel more sustainable is to develop hydrogen powered planes. The Soviets demonstrated this concept [1].

1. https://en.wikipedia.org/wiki/Tupolev_Tu-155


Yep - agree should pursue transformative solutions.

> The reality is, people aren't going to give up air travel.

I hear Fentanyl is pretty addictive as well - so might as well subsidized it and make it available to everyone cheaply, the downstream societal and health care costs are not the immediate problem - the problem is people want this stuff.....


Does fentanyl enable rapid transcontinental travel? Does it provide innumerable economic opportunities by enabling global social mobility?

>Air travel and freight is, by and large, is a luxury.

Flowers and f* ups get air freighted by plane, I've heard


Tragedy of the commons?

That’s hardly low carbon, container ships alone emit almost 20% of the CO2 we are putting into the atmosphere. And Cruise ships emit almost 4x as much as air travel per passenger.

You are off by an order of magnitude. Global oceanic shipping of all kinds is <3% of anthropogenic CO2[1]. Closer to 1.5-2% if you include land use changes.

You are correct about cruise ships, although it's more like 2-3x.

[1]: https://phys.org/news/2018-12-cargo-ships-emitting-boatloads...


Per KG of stuff moved it's pretty good.

Exactly - you need to decouple efficiency of mode, from amount of transport done in that mode if you want to make sensible decisions about which mode is best.

Or put it another way - if all that cargo going by sea went by air C02 emissions would be 100x more.

Obviously saying sea travel is massively more efficient doesn't obviate the need to reduce that as well.


but once you put people on it you f that number up.

Hang on I thought Cargo ships are the world's worst polluters? https://inews.co.uk/news/long-reads/cargo-container-shipping...

So for whatever reason, people are determined to confuse the issue here.

> It has been estimated that just one of these container ships, the length of around six football pitches, can produce the same amount of pollution as 50 million cars

"Pollution" here is defined to exclude CO2.

> And if the shipping industry were a country, it would be ranked between Germany and Japan as the sixth-largest contributor to global CO2 emissions.

And now a reference to CO2 to muddy the waters.

Shipping is highly CO2-efficient per kilo relative to air travel (and cars and so on) but because we do a _lot_ of shipping, it's still a big CO2 emitter. Separately, due to extremely shoddy international regulation, many large ships put out large amounts of non-CO2 pollutants. This (the non-CO2 bit, not the CO2 bit) could be fixed, at relatively small cost to the industry, via changes to fuel and improved filtering, but until someone forces them to fix it it'll stay the same.


There is one pollutant that oceanic shipping is worse at: SO2. SO2 happens to be a reverse-greenhouse gas, so it actually cancels out most of oceanic shipping's CO2. Because it creates smog and acid rain there is still a huge international push to reduce it, and the level of emissions have fallen by 80% in the past decade or so.

Comparing it to cars is very unfair. Gasoline in the 80s had tons of sulfur, FAR more than oceanic shipping emits today. It was totally eliminated by regulation and so that the sulfur can be sold at a profit. The relative difference is not relevant, because there's virtually no sulfur in car exhaust. Comparing the two tells you nothing about the absolute emissions or the recent and upcoming changes.

> And now a reference to CO2 to muddy the waters.

That's an understatement if anything- Japan and Germany are 3.5% and 2% of global CO2 respectively. It's preying on ignorance to make "6th most polluting country" sound high.

> This (the non-CO2 bit, not the CO2 bit) could be fixed, at relatively small cost to the industry, via changes to fuel and improved filtering, but until someone forces them to fix it it'll stay the same.

They are being forced- by the international maritime organization. The sulfur content has fallen from ~7.5% to an oceanic limit of at most 3.5% in 2012 (actual emissions are lower), falling to .5% this year. In the EU it's has been limited to .1% since 2015. Not least this is happening because China is taking such a hard line on smog. This is an incredible regulatory success, up there with leaded gasoline, iodized salt, and CFC bans.

It's very dangerous and detrimental to talk about oceanic shipping as a CO2 problem. It's essential to third world economies (both buying and selling), for one thing, but more importantly we know what the CO2 problems are: cars and coal. Fix those, then you can worry about natural gas and semi trucks. After that you've solved 80%-90% of the problem.

Seriously, say oceanic shipping globally is 2.5% of CO2 emissions. Light duty road vehicles are 59% of US transportation CO2, which is 29% of US CO2 emissions, which are 14% of of global CO2. Those multiply out to 2.4%. Forget trying to coordinate literally the entire world, you can get the same reductions by going after a single category of emissions from 4% of the world's population.


Like all other visually interesting aircraft, it will be quietly abandoned in a decade in favour of an A350++ or something.

>Such aircraft are complex to control but produce less aerodynamic drag, making them more efficient to fly.

Fuel effciency is big incentivising factor in the airline industry. If we can have an AI control the extra complexity involved to bring safety to a par I can see prototypes being made for further experiments. It is visually interesting though.


Yes, after the 737-MAX I absolutely want more computers, AI, blockchain, cloud, microservices, HTTP/3 and big data in the planes I'm boarding.

The problem with the 737-MAX was not that it used a computer. It was that the 737 series is generally not designed to be fly-by-wire and it was rammed in there to keep previous flight characteristics and just generally downplay the design ramifications of putting a much more massive engine below the wings that tilts the center of gravity considerably and changes flight characteristics.

Airbus is doing fine with fly-by-wire. They do so because they start with it at the design stage and don't haphazardly change major aerodynamic characteristics without going back to the drawing board and thinking through all the ramifications.

There is much more to say what went wrong and it's fairly well documented in public sources and little of it was because computers (though there is something to be said about the code quality culture at Boeing, but that's a different topic).


Interestingly though, main (sole?) purpose of MCAS was to reduce the cost of (re-)training human pilots, so the logic has kind of come full circle.

Airbus has been fully fly-by-wire for a long time now. It's one of the main differences with Boeing.

Those technologies are already used heavily by the airline industry which is extemely dependant on software and it probably will continue to build on that dependency.

Redundancy of flight controls with Kubernetes. If a flight control goes offline, Kubernetes auto-heals.

Maybe we can also have an AI that decides if you are carbon positive or carbon negative when you buy the plane ticket.

It perhaps could be connected to your car and phone, turning them off once you take a carbon positive flight.


Reminds me of the Boeing X-48B unmanned BWB: https://www.nasa.gov/centers/dryden/research/X-48B/index.htm...

And the Shell Oil concept plane model at Manchester's science museum: https://collection.sciencemuseumgroup.org.uk/objects/co84138...


From the model showing in the video, the aircraft has 2 vertical stabilizer mounted engines ala trijets (https://en.wikipedia.org/wiki/Trijet). Barring some smaller jets, this design has ceased in most large airliners for multiple reasons, one of them being the crash of United Flight 232(https://en.wikipedia.org/wiki/United_Airlines_Flight_232) where the Vert stabilizer mounted engine suffered an explosive dis-integration which in turn structurally damaged the tail sections as well as its hydraulic control lines, rendering the vert stab uncontrollable.

My guess would be the present design has many more significant iterations left.


I'm more interested in the E-Fan X aircraft shown. Looks like the BAe 146, which is probably my favorite plane of all time to fly in.

https://en.wikipedia.org/wiki/Airbus_E-Fan_X

I think it's exactly the BAe 146 :) One of my favourite planes also - I used to love flying early morning flights with DanAir from the North of England down to London back in the 80s... of course these days I'd just get the train.

I was reading up on the 146 a few months back, idly wondering how much one would cost - I think the reason they're using one here is that they're comparatively cheap on the used market as the number of engines makes them fairly expensive to service, but said number of engines obviously provides redundancy.


Regarding the turning problem. Why can’t they use the rudder more to turn and less tilting the plane?

Because that's not how flying works. When you apply rudder, you create a moment in the yaw axis, but that doesn't change the vector of the aircraft's speed/momentum. So your plane is still moving along its original vector, it's just not pointed straight at the direction it's moving anymore. This creates aerodynamic inefficiencies (which often self-correct) until eventually the plane's motion vector can be re-aligned to the direction it's pointing (completing a turn). Unfortunately, this is super inefficient. You're basically burning extra fuel to compensate for the aerodynamic inefficiencies you created by using the rudder only.

Plus, there may be some juddering/felt turbulation by the passengers, depending on how severe your induced yaw is. The passenger would also feel the plane pushing them to the side, rather than back and down into the seat as in a conventional turn.

Changing direction more conventionally is way more efficient, loads control surfaces less, is more consistent for passengers, and is pretty much better in every way.


Normally the ratio of rudder to tilt for a turn is fixed for a given aircraft. The main reason is that people are ok with experiencing downward forces, but not so much with sideways forces. As a pilot, if you want to keep the forces downward, you need to use both rudder and tilt in a particular combination. In order to make a turn you also really need a tilt - if you use only the rudder you are in a "slip", you don't really change your direction of movement but the direction of movement and the front of the plane are not aligned (actually it's more complicated and the rudder will initiate a tilt as well but I won't go there).

From what I understand, the problem with this particular kind of design is not so much about the direction of the forces but about the variation in forces though. If you're sitting in the end of a wing, as the aircraft goes into or out of a tilt you will experience quite some variation in the magnitude of the downward force, which is uncomfortable.


You do not really spend much time in cabin - you are either outside the ship during stops or in restaurants/bars/deck/pool during sea time. Inside cabins are often amazing value and work well if you do not have kids.


Boeing was looking at such designs around the time of the 787 program.

Whoever does manufacture one of these, I will bet you any amount of money that window seats will be at a large price premium, possibly even only for first class passengers.


The comment above movement in the article had me thinking... banking movements must feel scarier close to the windows on these types of planes.

True. So it may still be at the front of the plane (where the distance from centerline is still small). I could see a V shaped first class. Possible with a keystone-shaped galley, or a lounge.

The other problem is how do you get the toilets and the galley serviced from outside? And load the cargo bay?


This was a really cool attempt at a homebuilt BWB.

http://wingco.com/


Looks like that project suffered from the "hard to control" issue...

What is this? A plane for ants?!

What? They have built a model?

Call me a luddite but I feel unease at executives predicting the future of air travel depends on “disruptive technologies”

Disruptive technologies that are now commonplace in aviation:

- Jet engines

- Yaw damper

- Fly-by-wire

- ILS

- Composites

Among other minor inventions


The transportation industries are seriously planning on being disrupted in the next 5 - 10 years. Lots of telematics companies are, for example, betting on the fact that private vehicle ownership will be less of a thing within the next 2 - 10 years .. the sharing model will 'disrupt' things, etc.

You should not feel unease, but for sure try to imagine a world where ICE is phased out. This is going to happen. And when things get electric, they're going to get automatic ..


> Such aircraft are complex to control

I wonder if 737 Max is making them rethink this already. I love how it looks though.


There is nothing wrong with fly-by-wire and full authority controls as long as it is done correctly, it can even be more reliable than traditional mechanisms.

The way these things are made reliable is by redundancy and formal testing. The Boeing 737 Max MCAS had neither: it relied on a single angle of attack sensor and the software wasn't certified up to the appropriate level. The big mistake was that they gave the system more authority than what it was originally designed for, without an appropriate requalification.


Exactly. MCAS had only one goal: making the Boeing Max feel like the old Boeings by fiddling with the trim so that expensive retraining could be avoided. A fly by wire solution would have resulted in more design changes in the cockpit thus requiring a new type rating for lots of pilots.

IMHO it is entirely fixable technically but of course the scrutiny of the FAA on this and the resulting steady flow of management fuckups, more potential issues being unveiled, and the apparent failure of the certification process is pretty much guaranteeing this to take quite long. Last year I was still optimistic it would fly again soon but given the recent trickle of more issues, I think this is going to be a pro-longed grounding.

Airbus had it's fair share of incidents involving fly by wire in the eighties and nineties. However, more recent incidents seem to be not related to that anymore (terrorist attacks, bird strikes, bad weather/decision making, etc.). So, fly by wire is entirely safe if done properly these days and also not optional for flying most modern military planes. Airbus basically laid the foundation for their current success in the market right then.

IMHO pilots are increasingly becoming safety pilots (i.e. emergencies and unusual situations are the only times they fly manually) and we're not that long away from fully autonomous planes. Right now, aside from takeoff and landing, most passenger planes are controlled via the auto pilot only. The pilot doesn't touch the yoke and instead fiddles with buttons to direct the auto pilot. Cat III landings can be fully automated technically and certified pilots are required to fly a certain amount of fully automated touchdowns regularly. The military routinely flies remotely controlled drones and fully autonomous drones already.

So, a design like this could make sense. 20% reduction in drag is quite a lot of gain and fly by wire has been used for decades to make all sorts of otherwise unstable configurations flyable.


The 737 Max situation (among other things) stems from trying to cram a complex system into an existing simpler one while staying within existing constraints to avoid recertification.

With a new design "from scratch" like this which would need new certification anyway, this wouldn't be an issue.


This has absolutely nothing to do with the 737 Max.

Airbus in particular has been using fly-by-wire for years. The issue with the 737 Max is that it felt different to control under different flight conditions from the classic 737 and Boeing tried to patch that difference in software. There would be no such issue in a new from-the-CAD-file-up airframe.


And there are failure modes where solution is basically reboot the computer. This would not go well in wing body design.

How is this any different from current Airbus planes? They are all fly by wire. If you turn off the computer in them you will lose all control. This is why they have a bunch of redundancy built in.

There is some level of mechanical control. The airframe is stable in wing design computer is continuously adjusting control surfaces it's not flyable by a human.

Maybe you should tell that to Northrup Grumman.

Are you saying Airbus is equipping planes with ejection seats like Northrup Grumman?

Are you saying that ejection seats are considered safe for use when your computer fails?

It’s not controlled by flight computer

Airbus has a lot of experience with fly-by-wire. The problem with the 737 MAX wasn't fly-by-wire as such.

If they're going all in on a radical new design, and especially if it might only be for cargo, why not get rid of the pilots?

Because people will not fly a plane that has no pilot. One of the largest scandals in aviation history was unveiled only recently and it was caused by software issues, not the human factor as mostly is the case. We're not there yet and pretending we are won't make it so.

Um. On long flights, apparently the pilots are mostly asleep. So 'nobody' includes a lot of people, practically.

The pilots are definitely not "mostly asleep" on long flights. There will be two qualified pilots monitoring the aircraft at all times during the flight (with the possible exception of one stepping out for a moment to use the restroom during cruise). Long haul flights will carry relief crew, 3 or even 4 pilots total, so they can take shifts flying the aircraft.

Being asleep in the cockpit is a good way to quickly end your flying career.


When you're aloft, you are safe unless the plane is depressurized or on fire. The key safety feature in aviation is the manner in which the plane returns to the earth. This is a job for humans to manage.

Some pilots stop paying attention on long, boring stretches where the autopilot is fully capable of following a vector and an altitude. However, if there's an alarm due to control issue or other emergency, the human is alerted and would take over amyway. That's why it's called an alarm. I don't mean to imply that I support this behavior, but it is an understandable human factor that's a lower priority to correct than other safety factors.


That's actually being suggested for battery-powered commuter planes -- low capacity & range means bigger impact from more paying load.

It's also being researched, as well as single pilot operation.

What about patents? I’d be surprised if Boeing don’t own patents in every possible field related to this type of design, given their history with this type of aircraft.

It’s a nice idea, but I can’t see it ever being anything other than a loud argument. Maybe that’s the point - airbus trying to lure Boeing into a battle they think they can win (legal) when it turns out it’s actually an ambush in the PR war.


Eh? Boeing has made prototypes that look vaguely like this in the past, but the patents would long since have expired. And you can't patent visual design. If Boeing makes a weirdly short stubby aircraft, Airbus can't sue them for copying their A318 concept, say.

Those patents would likely have expired already.

I would bet that Airbus and Boeing have to cross-license their patents to one another anyway. Their interest is in keeping other entrants out of the market.


patents are typically valid for 20 years or so depending on jurisdiction. So unless Boeing has done a bunch of research/patenting after the year 2000 is not something to worry about.

There have been a lot of flying wings or blended wing bodies through history. Horten (Germany) in the 30s and 40s, Northrop since the 40s and some russian models from 30s and 40s as well. The concept isn't that new. It just didn't make that much sense so far in non-military, non-stealth applications. Excluding UAVs, the B-2 has build the most with 21, followed by the Horten H.III gluider from WW2 with 19 or so.

One issue could be airport infrastructure, the wing span would take up a lot of terminal / gate space. But if these planes are economically enough, who knows?


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