5 ms·

And yet new airframes do get certified.

by tekla 3y ago

JumpCrisscross 3y ago
> yet new airframes do get certified Last one was the 737 Max in 2017. It’s a derivative. The last truly new frames were the 787 in 2011 and A380 in 2006. Both focussed on subsystems, propulsion and materials for their novelty; only one has been a commercial success. One successful (two attempted) new airframes in over two decades is extraordinarily slower than the pre-consolidation frequency. It is also notable that neither attempted to introduce a new air frame that directly competes with the other’s; Airbus and Boeing trade market segments. There is zero head-to-head competition. Modern planes are a marvel of engineering. And newer planes are more comfortable. That doesn’t change that we’re stuck in a local optimum due to a cessation of risk taking.
- tekla 3y ago
  Why do you keep thinking competition is what prevented blended wing bodies? Blended wing bodies make big trade offs that don't neatly fit with commercial flight. The analysis of different lifting bodies is fairly fundamental aeronautical engineering work every student learns. There is no weird conspiracy here.
  - JumpCrisscross 3y ago
    > Why do you keep thinking competition is what prevented blended wing bodies? Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation. > no weird conspiracy Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction.
    - tekla 3y ago
      > Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation. Bullshit. There is tons of money for innovation, every single manufacturer is trying to squeeze 1-2% efficient improvements across the board. To say there is no funding for innovation is hilariously ignorant. > Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction. Cool, can you show me what numbers you're looking at that even hint that these blended wing bodies are better than contemporary commercial designs?
      - JumpCrisscross 3y ago
        > Bullshit. There is tons of money for innovation I heard almost the same out of a Lockheed executive about launch about a decade and a half ago. A dollar of R&D can travel differently at a cushy corporation than at one in competition. > can you show me what numbers you're looking at that even hint that these blended wing bodies are better No, I have never defended this design—I have no specs. A better question is why you’re so convinced this optimum is the global one.
      - dragonwriter 3y ago
        > Cool, can you show me what numbers you’re looking at that even hint that these blended wing bodies are better than contemporary commercial designs? Department of the Air Force Climate Action Plan, October 2022 [0] (p17) “For example, development of blended wing body aircraft could drive transformative changes, as this aircraft design increases aerodynamic efficiency by at least 30 percent over current Air Force tanker and mobility aircraft” [Note that Air Force tanker and mobility aircraft are similar to, and in some cases simply militarized versions of, commercial airliner or air transport designs.] The same report (p19) identifies development and testing of a full-scale blended wing prototype by FY27 as a Key Result of the Action Plan. [0] https://www.safie.hq.af.mil/Portals/78/documents/Climate/DAF%20CAP%20Dec%2023%20Mod.pdf?ver=eWS2AgUkpuQBFOlIbcIkew%3d%3d https://www.safie.hq.af.mil/Portals/78/documents/Climate/DAF... [PDF]
    - dragonwriter 3y ago
      > OP asked why all planes since the 70s look about the same. All commercial passenger airliners (and there are some exceptions there, but in different directions than blended-wing-body) look about the same, but not all airplanes do. > It’s because there isn’t a sustained budget for experimentation. No, its because there are various technical challenges with blended wing-body aircraft that have to be balanced against the reduced drag and resulting better fuel efficiency, such as structural challenges if you want continuous internal cabin space; access if you want to be able to evacuate them as efficiently as a tubular fuselage aircraft, etc. Some of those have had progress over the years (e.g., the structural ones) as material science has advanced. There are blended-wing-body designs (or the related but more extreme flying wing design) that have been produced, mostly as experimental or military aircraft (several US strategic bombers have been blended-wing-body or flying wing designs: the B-1 is a blended-wing-body (also with variable sweep wings), B-2 and B-21 are flying wing designs.)
- notahacker 3y ago
  There's been more competition in the regional market including clean sheet designs by new entrants, but they're all conventional tubes and wings and podded turbofans too. China's state funded A320/737 competitor is a clone with a shared engine platform too. Improving on current generation airliners is hard compared with improving what flew between 1920 and 1950, and consolidation happened because it wasn't profitable. Airlines and financiers don't like uncertainty either.
- ClarkMarx 3y ago
  The A350, a clean sheet composite design, was certified in 2014.
  - JumpCrisscross 3y ago
    You’re right. The A220 and A350 were clean sheets introduced in the 2010s.
- Ekaros 3y ago
  A220 in 2015 I think was also clean sheet.

And yet new airframes do get certified.

by tekla 3y ago

And yet new airframes do get certified.

> yet new airframes do get certified Last one was the 737 Max in 2017. It’s a derivative. The last truly new frames were the 787 in 2011 and A380 in 2006. Both focussed on subsystems, propulsion and materials for their novelty; only one has been a commercial success. One successful (two attempted) new airframes in over two decades is extraordinarily slower than the pre-consolidation frequency. It is also notable that neither attempted to introduce a new air frame that directly competes with the other’s; Airbus and Boeing trade market segments. There is zero head-to-head competition. Modern planes are a marvel of engineering. And newer planes are more comfortable. That doesn’t change that we’re stuck in a local optimum due to a cessation of risk taking.

tekla 3y ago
Why do you keep thinking competition is what prevented blended wing bodies? Blended wing bodies make big trade offs that don't neatly fit with commercial flight. The analysis of different lifting bodies is fairly fundamental aeronautical engineering work every student learns. There is no weird conspiracy here.
- JumpCrisscross 3y ago
  > Why do you keep thinking competition is what prevented blended wing bodies? Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation. > no weird conspiracy Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction.
  - tekla 3y ago
    > Never said as much. OP asked why all planes since the 70s look about the same. It’s because there isn’t a sustained budget for experimentation. Bullshit. There is tons of money for innovation, every single manufacturer is trying to squeeze 1-2% efficient improvements across the board. To say there is no funding for innovation is hilariously ignorant. > Never said as much. It’s not exactly groundbreaking for entrenched supplies to cease innovating and focus on extraction. Cool, can you show me what numbers you're looking at that even hint that these blended wing bodies are better than contemporary commercial designs?
    - JumpCrisscross 3y ago
      > Bullshit. There is tons of money for innovation I heard almost the same out of a Lockheed executive about launch about a decade and a half ago. A dollar of R&D can travel differently at a cushy corporation than at one in competition. > can you show me what numbers you're looking at that even hint that these blended wing bodies are better No, I have never defended this design—I have no specs. A better question is why you’re so convinced this optimum is the global one.
    - dragonwriter 3y ago
      > Cool, can you show me what numbers you’re looking at that even hint that these blended wing bodies are better than contemporary commercial designs? Department of the Air Force Climate Action Plan, October 2022 [0] (p17) “For example, development of blended wing body aircraft could drive transformative changes, as this aircraft design increases aerodynamic efficiency by at least 30 percent over current Air Force tanker and mobility aircraft” [Note that Air Force tanker and mobility aircraft are similar to, and in some cases simply militarized versions of, commercial airliner or air transport designs.] The same report (p19) identifies development and testing of a full-scale blended wing prototype by FY27 as a Key Result of the Action Plan. [0] https://www.safie.hq.af.mil/Portals/78/documents/Climate/DAF%20CAP%20Dec%2023%20Mod.pdf?ver=eWS2AgUkpuQBFOlIbcIkew%3d%3d https://www.safie.hq.af.mil/Portals/78/documents/Climate/DAF... [PDF]
  - dragonwriter 3y ago
    > OP asked why all planes since the 70s look about the same. All commercial passenger airliners (and there are some exceptions there, but in different directions than blended-wing-body) look about the same, but not all airplanes do. > It’s because there isn’t a sustained budget for experimentation. No, its because there are various technical challenges with blended wing-body aircraft that have to be balanced against the reduced drag and resulting better fuel efficiency, such as structural challenges if you want continuous internal cabin space; access if you want to be able to evacuate them as efficiently as a tubular fuselage aircraft, etc. Some of those have had progress over the years (e.g., the structural ones) as material science has advanced. There are blended-wing-body designs (or the related but more extreme flying wing design) that have been produced, mostly as experimental or military aircraft (several US strategic bombers have been blended-wing-body or flying wing designs: the B-1 is a blended-wing-body (also with variable sweep wings), B-2 and B-21 are flying wing designs.)
notahacker 3y ago
There's been more competition in the regional market including clean sheet designs by new entrants, but they're all conventional tubes and wings and podded turbofans too. China's state funded A320/737 competitor is a clone with a shared engine platform too. Improving on current generation airliners is hard compared with improving what flew between 1920 and 1950, and consolidation happened because it wasn't profitable. Airlines and financiers don't like uncertainty either.
ClarkMarx 3y ago
The A350, a clean sheet composite design, was certified in 2014.
- JumpCrisscross 3y ago
  You’re right. The A220 and A350 were clean sheets introduced in the 2010s.
Ekaros 3y ago
A220 in 2015 I think was also clean sheet.