7 ms·

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 t

by rob74 7y ago

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.

01CGAT 7y ago
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.
- rob74 7y ago
  Let me quote from the Wikipedia article https://en.wikipedia.org/wiki/Lockheed_Constellation 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...
  - londons_explore 7y ago
    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.
    - throwanem 7y ago
      Yeah, a passenger aircraft is somewhat more complex in manufacture than a MacBook Pro.
    - PietdeVries 7y ago
      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...
      - lowdose 7y ago
        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.
        mediaman 7y ago
        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.
      - himinlomax 7y ago
        3D printing.
    - jbay808 7y ago
      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.
- digikata 7y ago
  I imagine even larger gantry variant of this carbon fiber loom: https://www.youtube.com/watch?v=j19na8LMBnE https://www.youtube.com/watch?v=j19na8LMBnE
- deleted 7y ago
  [deleted]
hinkley 7y ago
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.
- AnimalMuppet 7y ago
  Not just "across Seattle". From Wichita to Seattle.

by rob74 7y ago

01CGAT 7y ago

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.

rob74 7y ago
Let me quote from the Wikipedia article https://en.wikipedia.org/wiki/Lockheed_Constellation 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...
- londons_explore 7y ago
  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.
  - throwanem 7y ago
    Yeah, a passenger aircraft is somewhat more complex in manufacture than a MacBook Pro.
  - PietdeVries 7y ago
    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...
    - lowdose 7y ago
      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.
      - mediaman 7y ago
        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.
    - himinlomax 7y ago
      3D printing.
  - jbay808 7y ago
    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.
digikata 7y ago
I imagine even larger gantry variant of this carbon fiber loom: https://www.youtube.com/watch?v=j19na8LMBnE https://www.youtube.com/watch?v=j19na8LMBnE
deleted 7y ago
[deleted]

hinkley 7y ago

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.

AnimalMuppet 7y ago
Not just "across Seattle". From Wichita to Seattle.