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Interesting historical note on the blended wing design: One of the main arguments against it was that designers weren't sure if people would be ok with sitting

Interesting historical note on the blended wing design: One of the main arguments against it was that designers weren't sure if people would be ok with sitting towards the center of the plane. The thought was that passengers wouldn't be comfortable without being able to at least see outside (even a little, looking at you 3/4/3 widebody planes). I mention this b/c there is a quote in Mary Roach's Flying to Mars. She mentions concerns around how astronauts will be able to psychologically handle the remoteness of space. As a similar example. they talk about how in Victorian England people were concerned that trains would be traveling so quickly that it would induce a state of shock in the passengers. This turned out to not be the case at all. In fact, she quotes a cosmonaut who says "Only people think this is problem is psychologists".

nervousvarun 4y ago
This "problem" goes away if you just have one of the feeds in the seat-back entertainment system be a wing mounted camera view no?
- kridsdale2 4y ago
  Maybe if you had it in stereo 3D and gave the passengers a VR display.
- tengbretson 4y ago
  If that were true, why would the person be on the plane in the first place? Couldn't they just watch a movie of their destination or zoom call the person they were visiting from home?
  - nordsieck 4y ago
    > If that were true, why would the person be on the plane in the first place? Couldn't they just watch a movie of their destination or zoom call the person they were visiting from home? It can be the case that both: * watching a video of the plane moving through the air is an effective way to mitigate some of the discomfort of flying * meeting face to face with someone is valuable enough that it's worth taking the flight
  - ikrenji 4y ago
    ? people go on planes to get to places not to experience flight itself per se. i don't mind sitting in an enclosed room for x amount of hours while it gets me half-way across the world for cheap
nicktelford 4y ago
A bigger problem with blended wing designs is actually for the people on the peripheral. When the plane banks, passengers further from the axis of rotation will feel a more significant change in their altitude. You literally feel like you're "falling", as the plane banks to your side. This also applies to existing aircraft, but the amount you drop/rise is limited by the your distance from the axis of rotation, which is normally not very far. In blended wing designs, the distance could be considerably greater, making this sensation much more intense. The workaround for this would be to simply use shallower bank angles, but I suspect that would require some pretty major changes to navigation rules, as it would drastically increase the turn radius.
- chrisBob 4y ago
  The issue isn't the bank angle exactly, it is the acceleration of the roll. Pilots will need to be careful not to throw people or drinks around, but I think it would be doable.
  - aaronblohowiak 4y ago
    depends on the flight paths for different airports. some require tighter turns.
  - dan_quixote 4y ago
    Pilots can control the bank acceleration, sure. They have much less control over acceleration due to uneven turbulence.
    - thot_experiment 4y ago
      I'm not sure this tracks, I think turbulence powerful enough to cause passenger discomfort is usually so big that it affects the whole plane pretty uniformly. I think it's exceedingly unlikely that you'll spend enough time on a shear line to induce a large roll. At least it's never happened to me, but I am only a passenger.
      - 4y ago
jcampbell1 4y ago
The main argument against it is that it increases fuel consumption. Plowing your cargo area through the air sideways is just idiotic. There is some crazy public belief that it is more fuel efficient because the public doesn’t understand physics. These things keep getting getting publicity because even Hacker News folks don’t get it. Long high aspect ratio wings and streamlined body are how you get fuel efficiency. The fuel burn of a B2 is far higher pound for pound than a 737. This idea gets even more ridiculous when you consider the cargo area is a pressure vessel. There is a reason the body is isomorphic with a welding tank. Edit: I suppose I wouldn’t care about this, but the Biden Administration plowed climate money into a blended wing military concept, which 1 day with any CFD software shows is stupid.
- strongpigeon 4y ago
  You seem knowledgeable about this. Do you mind expanding on why these aren’t more efficient?
  - kridsdale2 4y ago
    I'm no aerospace engineer, but the flux through the air, driving resistance, seems obviously higher the more you move away from the shape of a missile.
  - schiffern 4y ago
    The problem is frontal area is higher, so more drag. Wetted area[1] is also much higher, so there's a lot of skin friction. The advantages are (theoretically) lower structure mass per passenger. But airplane cabins are pressurized, and lightweight pressure vessels 'want' to be cylinders or spheres, not big flat boxes. There's a aerospace engineering student who gave a thesis talk on the disadvantages of blended wing-body, and offers some possible solutions.[2] [1] https://en.wikipedia.org/wiki/Wetted_area https://en.wikipedia.org/wiki/Wetted_area [2] https://www.youtube.com/watch?v=IWBaddGG6z8 https://www.youtube.com/watch?v=IWBaddGG6z8
- coredog64 4y ago
  It’s not that simple. Aerodynamic drag is made up of surface drag and induced drag. Given the same coefficient of drag, drag goes up as S-wet goes up (which is what you’re referencing). Induced drag is a consequence of how much structure is required to create a flying vehicle. IF (and it’s a big if) the BWB turns out to be more structurally efficient, then the total drag for the plane might be less than for a conventional design. (Source: I have an aerospace engineering degree from Embry-Riddle)
JustSomeNobody 4y ago
Anecdotally, I hate flying if I can't see out the window. Like, really really hate it.
- blamazon 4y ago
  My experience as a frequent flyer is that First Class is the most likely cabin to have all windows closed for 100% of the flight. It's baffling to me, people will even keep closed the window facing New York on the approach to LaGuardia which should be a crime. Also Boston, Salt Lake, Hawaii, and really pretty much all places except like Dallas and Cleveland types totally perplex me when the window is closed and I'm not directly next to it. I want to witness this glorious rock from above!
  - horsawlarway 4y ago
    I see this more and more everywhere across the plane these days. I remember flying as a kid/teen and nearly every window was open during takeoff and touchdown. Last 3 to 5 years and almost every flight has had less than 10% of the windows open. I don't get it - I also want to see it. We're fucking flying, for god's sake.
    - willcipriano 4y ago
      They didn't have the magical rectangle when you were a kid. Might miss some celebrity vacation pics if you take your eyes off it.
    - culopatin 4y ago
      I thought I was the only one who experienced this. I race cars as a hobby but I suffer from motion sickness whenever I’m not driving or whenever I can’t see out. People will choose the window seat and keep it closed the whole time. WHY?! At least open it when we’re on the ground being shaken back and forth while backing out and taxiing so my mind doesn’t lose point of reference.
    - aeternum 4y ago
      They used to ask you to open the window shades for takeoff and landing, idea was to actually be aware of what is going on outside incase an evac is necessary. Now they ask everyone only to close the window shades after landing to better control the temp, the APU a/c is often no match for direct sunlight. Then most people just leave them closed.
VBprogrammer 4y ago
My understanding is that having to manufacture a different rib for each station along the structure is a significant challenge. It's possibly less of an issue with composites?
- scarier 4y ago
  The differences in ribs across the span of a wing are much less of an issue than compound curvature in the wing skins—this is where composite manufacturing really shines, because you can mold them into arbitrary shapes.
  - deleted 4y ago
    [deleted]
- dan_quixote 4y ago
  The ribs are already all different across existing commercial airplane wings.
  - VBprogrammer 4y ago
    Across the wings yes but not across the majority of the fuselage.
    - scarier 4y ago
      How is that a meaningful distinction from either a design or manufacturing standpoint?
      - dr_orpheus 4y ago
        Because the fuselage is pressurized. And it is convenient to have pressure vessels as cylinders for even distribution of of the pressure forces across it. Ideally you want to have it capped off with two hemispheres (think propane tank shaped) but obviously you can't do that for other reasons. So there is likely more design and manufacturing for the front and rear of the plane than the main section.
brokencode 4y ago
Personally, the only things I care about in a plane are safety (by a wide margin), comfort, and price. I spend all my time listening to music with my eyes closed or watching movies anyway, and the window doesn’t give me much. Maybe just put a bunch of cameras all over the exterior so the passengers can see what’s going on wherever they are sitting.
- robotresearcher 4y ago
  I hear you. But the first time I did a polar/Hudson Bay flight between Europe and west coast USA, I was transfixed by the view out of the window. I’m very happy to have seen that extraordinarily beautiful view. Cameras would be some compensation, but the direct view is amazing. Arguably not as spectacular, but I relish every city approach. The serpentine Thames as you stack over Heathrow, the mountains of Vancouver, the insane scale of Tokyo: I value fuel and cost savings, but I hope there will always be opportunities to experience these wonderful views.
  - brokencode 4y ago
    Planes have a huge impact on both the climate and economy, and I don’t think the joy of occasional sightseeing is a strong enough argument against pursuing efficiency gains.

nervousvarun 4y ago

This "problem" goes away if you just have one of the feeds in the seat-back entertainment system be a wing mounted camera view no?

kridsdale2 4y ago
Maybe if you had it in stereo 3D and gave the passengers a VR display.
tengbretson 4y ago
If that were true, why would the person be on the plane in the first place? Couldn't they just watch a movie of their destination or zoom call the person they were visiting from home?
- nordsieck 4y ago
  > If that were true, why would the person be on the plane in the first place? Couldn't they just watch a movie of their destination or zoom call the person they were visiting from home? It can be the case that both: * watching a video of the plane moving through the air is an effective way to mitigate some of the discomfort of flying * meeting face to face with someone is valuable enough that it's worth taking the flight
- ikrenji 4y ago
  ? people go on planes to get to places not to experience flight itself per se. i don't mind sitting in an enclosed room for x amount of hours while it gets me half-way across the world for cheap

nicktelford 4y ago

A bigger problem with blended wing designs is actually for the people on the peripheral. When the plane banks, passengers further from the axis of rotation will feel a more significant change in their altitude. You literally feel like you're "falling", as the plane banks to your side. This also applies to existing aircraft, but the amount you drop/rise is limited by the your distance from the axis of rotation, which is normally not very far. In blended wing designs, the distance could be considerably greater, making this sensation much more intense. The workaround for this would be to simply use shallower bank angles, but I suspect that would require some pretty major changes to navigation rules, as it would drastically increase the turn radius.

chrisBob 4y ago
The issue isn't the bank angle exactly, it is the acceleration of the roll. Pilots will need to be careful not to throw people or drinks around, but I think it would be doable.
- aaronblohowiak 4y ago
  depends on the flight paths for different airports. some require tighter turns.
- dan_quixote 4y ago
  Pilots can control the bank acceleration, sure. They have much less control over acceleration due to uneven turbulence.
  - thot_experiment 4y ago
    I'm not sure this tracks, I think turbulence powerful enough to cause passenger discomfort is usually so big that it affects the whole plane pretty uniformly. I think it's exceedingly unlikely that you'll spend enough time on a shear line to induce a large roll. At least it's never happened to me, but I am only a passenger.
    - 4y ago

jcampbell1 4y ago

The main argument against it is that it increases fuel consumption. Plowing your cargo area through the air sideways is just idiotic. There is some crazy public belief that it is more fuel efficient because the public doesn’t understand physics. These things keep getting getting publicity because even Hacker News folks don’t get it. Long high aspect ratio wings and streamlined body are how you get fuel efficiency. The fuel burn of a B2 is far higher pound for pound than a 737. This idea gets even more ridiculous when you consider the cargo area is a pressure vessel. There is a reason the body is isomorphic with a welding tank. Edit: I suppose I wouldn’t care about this, but the Biden Administration plowed climate money into a blended wing military concept, which 1 day with any CFD software shows is stupid.

strongpigeon 4y ago
You seem knowledgeable about this. Do you mind expanding on why these aren’t more efficient?
- kridsdale2 4y ago
  I'm no aerospace engineer, but the flux through the air, driving resistance, seems obviously higher the more you move away from the shape of a missile.
- schiffern 4y ago
  The problem is frontal area is higher, so more drag. Wetted area[1] is also much higher, so there's a lot of skin friction. The advantages are (theoretically) lower structure mass per passenger. But airplane cabins are pressurized, and lightweight pressure vessels 'want' to be cylinders or spheres, not big flat boxes. There's a aerospace engineering student who gave a thesis talk on the disadvantages of blended wing-body, and offers some possible solutions.[2] [1] https://en.wikipedia.org/wiki/Wetted_area https://en.wikipedia.org/wiki/Wetted_area [2] https://www.youtube.com/watch?v=IWBaddGG6z8 https://www.youtube.com/watch?v=IWBaddGG6z8
coredog64 4y ago
It’s not that simple. Aerodynamic drag is made up of surface drag and induced drag. Given the same coefficient of drag, drag goes up as S-wet goes up (which is what you’re referencing). Induced drag is a consequence of how much structure is required to create a flying vehicle. IF (and it’s a big if) the BWB turns out to be more structurally efficient, then the total drag for the plane might be less than for a conventional design. (Source: I have an aerospace engineering degree from Embry-Riddle)

JustSomeNobody 4y ago

Anecdotally, I hate flying if I can't see out the window. Like, really really hate it.

blamazon 4y ago
My experience as a frequent flyer is that First Class is the most likely cabin to have all windows closed for 100% of the flight. It's baffling to me, people will even keep closed the window facing New York on the approach to LaGuardia which should be a crime. Also Boston, Salt Lake, Hawaii, and really pretty much all places except like Dallas and Cleveland types totally perplex me when the window is closed and I'm not directly next to it. I want to witness this glorious rock from above!
- horsawlarway 4y ago
  I see this more and more everywhere across the plane these days. I remember flying as a kid/teen and nearly every window was open during takeoff and touchdown. Last 3 to 5 years and almost every flight has had less than 10% of the windows open. I don't get it - I also want to see it. We're fucking flying, for god's sake.
  - willcipriano 4y ago
    They didn't have the magical rectangle when you were a kid. Might miss some celebrity vacation pics if you take your eyes off it.
  - culopatin 4y ago
    I thought I was the only one who experienced this. I race cars as a hobby but I suffer from motion sickness whenever I’m not driving or whenever I can’t see out. People will choose the window seat and keep it closed the whole time. WHY?! At least open it when we’re on the ground being shaken back and forth while backing out and taxiing so my mind doesn’t lose point of reference.
  - aeternum 4y ago
    They used to ask you to open the window shades for takeoff and landing, idea was to actually be aware of what is going on outside incase an evac is necessary. Now they ask everyone only to close the window shades after landing to better control the temp, the APU a/c is often no match for direct sunlight. Then most people just leave them closed.

VBprogrammer 4y ago

My understanding is that having to manufacture a different rib for each station along the structure is a significant challenge. It's possibly less of an issue with composites?

scarier 4y ago
The differences in ribs across the span of a wing are much less of an issue than compound curvature in the wing skins—this is where composite manufacturing really shines, because you can mold them into arbitrary shapes.
- deleted 4y ago
  [deleted]
dan_quixote 4y ago
The ribs are already all different across existing commercial airplane wings.
- VBprogrammer 4y ago
  Across the wings yes but not across the majority of the fuselage.
  - scarier 4y ago
    How is that a meaningful distinction from either a design or manufacturing standpoint?
    - dr_orpheus 4y ago
      Because the fuselage is pressurized. And it is convenient to have pressure vessels as cylinders for even distribution of of the pressure forces across it. Ideally you want to have it capped off with two hemispheres (think propane tank shaped) but obviously you can't do that for other reasons. So there is likely more design and manufacturing for the front and rear of the plane than the main section.

brokencode 4y ago

Personally, the only things I care about in a plane are safety (by a wide margin), comfort, and price. I spend all my time listening to music with my eyes closed or watching movies anyway, and the window doesn’t give me much. Maybe just put a bunch of cameras all over the exterior so the passengers can see what’s going on wherever they are sitting.

robotresearcher 4y ago
I hear you. But the first time I did a polar/Hudson Bay flight between Europe and west coast USA, I was transfixed by the view out of the window. I’m very happy to have seen that extraordinarily beautiful view. Cameras would be some compensation, but the direct view is amazing. Arguably not as spectacular, but I relish every city approach. The serpentine Thames as you stack over Heathrow, the mountains of Vancouver, the insane scale of Tokyo: I value fuel and cost savings, but I hope there will always be opportunities to experience these wonderful views.
- brokencode 4y ago
  Planes have a huge impact on both the climate and economy, and I don’t think the joy of occasional sightseeing is a strong enough argument against pursuing efficiency gains.