Designing a very, very large airliner…
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I agree that initially, standard seating on the DC-10 and B777 was 2-5-2. But the DC-10 went away, and seating on the B777 has generally changed to 3-3-3 (or 3-4-3, a configuration that I avoid like the plague).
I still believe that despite a huge increase in emergency exit doors, you will still need double-wide aisles in order to have efficient PAX loading and unloading, as well as avoiding complete aisle blockage by service trolleys.
I still believe that despite a huge increase in emergency exit doors, you will still need double-wide aisles in order to have efficient PAX loading and unloading, as well as avoiding complete aisle blockage by service trolleys.
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I agree that initially, standard seating on the DC-10 and B777 was 2-5-2. But the DC-10 went away, and seating on the B777 has generally changed to 3-3-3 (or 3-4-3, a configuration that I avoid like the plague).
I still believe that despite a huge increase in emergency exit doors, you will still need double-wide aisles in order to have efficient PAX loading and unloading, as well as avoiding complete aisle blockage by service trolleys.
I still believe that despite a huge increase in emergency exit doors, you will still need double-wide aisles in order to have efficient PAX loading and unloading, as well as avoiding complete aisle blockage by service trolleys.
Maybe increased aisle width, yes. But double aisle width is I think overkill. Each deck is about the size of your average B777-300 so I don't see why double-width aisles are necessary. And at 11-abreast (lower and main deck), 26in width each aisle is available.
OFF TOPIC: Doesn't forums have quote buttons so you can show the name of the person you are quoting?
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Originally Posted by medviation
I'm confident evacuation wouldn't be a problem since I configured my aircraft with sufficient exits per deck. The aircraft would have 4 pairs of type A doors on the upper deck, 5 on the main deck and 6 on the lower deck.[...]
Even though: An aircraft is not an flying house, there is a reason that the evacuation is live tested for certification.
Originally Posted by medviation
If you want more, go for premium econ or business class.
Originally Posted by medviation
OFF TOPIC: Doesn't forums have quote buttons so you can show the name of the person you are quoting?
Greetings,
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Do you have any clue how that plus the long distance between the wings would influence the structural analysis?
Even though: An aircraft is not a flying house, there is a reason that the evacuation is live tested for certification.
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Originally Posted by medviation
No I don't have a clue. I'm just a scruffy guy with no engineering or flying experience who hides in his room most of the day. I'm bringing this up for help with the analysis.
When you discuss an idea, it is not the person under criticism, it is the idea.
If you get a tip about an limitation you have to change it, or set an IF.
e.g.: IF the neutral point stays within the limits whilst using pitch.
Too many IFs are pushing the project from hard to manage to science fiction.
As I already said, it is mainly the distance between the fixpoints of the wings that gets this project to Science fiction. With this layout the project gets the following IFs:
IF the structural analysis is sober with consideration of turbulences,
IF the neutral point of lift stays within the limits,
IF the aeroelastic layout is done properly or new meterials appear,
IF someone needs an newly designed aircraft with the capacy of 2 A380s,
IF the airports get to manage the newly type of aircraft,
the plane could be built.
As you may have seen, even the Cranfield study has not this much space between the wings, you should think a bit of it. I mentioned already that aeroelastics may be a lot of a problem, this layout might work in a wingspan from 20-30 meters, 80 meters is sheer to much bravery.
Greetings,
Last edited by Sokol; 17th Feb 2016 at 10:27.
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What is the drawback of having a dual wing layout like a traditional Biplane?
If wing length is the issue, then why not put half the wing directly on top of the other half, possibly joining the two wingtips to reduce the vortex effects?
If wing length is the issue, then why not put half the wing directly on top of the other half, possibly joining the two wingtips to reduce the vortex effects?
I can just imagine the fun finding HOTAC for 1,600 pax in the event of a delayed/diverted/cancelled flight.
Originally Posted by sallyann
I can just imagine the fun finding HOTAC for 1,600 pax in the event of a delayed/diverted/cancelled flight.
Then, you have 5 days to work through the queue. After 24 hours, those at the head of the queue will be checking out and those rooms can be re-allocated.
Thus only about 320 rooms are needed.
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I did a simple wingflex model to see how the wing would flex. I saw several issues with the bending motion especially on the wing brace that joins the two wings. Constant and extreme bending and twisting of the brace could lead to eventual failure of the wing structure if made of conventional aluminum or composite materials and structure.
Having a background in architecture, I know of a technology used for earthquake-proofing buildings that could be applied here. This plastic/rubber bearing isolates the building from the foundation so when an earthquake occurs, the building can just dance around and not crack.
A similar setup can be used to isolate the wingtip brace from the rest of the wings. This should allow the two wings to twist and bend without having to put too much pressure on the wingtip. This could be engineered to still have a certain amount of resistance so the two wings can still share loads.
Another area I might put in question is how this could react in flutter. Perhaps the two wings could be designed to oscillate in a different frequency to dampen out potentially dangerous vibrations?
Having a background in architecture, I know of a technology used for earthquake-proofing buildings that could be applied here. This plastic/rubber bearing isolates the building from the foundation so when an earthquake occurs, the building can just dance around and not crack.
A similar setup can be used to isolate the wingtip brace from the rest of the wings. This should allow the two wings to twist and bend without having to put too much pressure on the wingtip. This could be engineered to still have a certain amount of resistance so the two wings can still share loads.
Another area I might put in question is how this could react in flutter. Perhaps the two wings could be designed to oscillate in a different frequency to dampen out potentially dangerous vibrations?
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Yeah, that's a personal preference of aviation guys like us. But for most people who just want to fly for cheap, they don't care much if it's a 2-5-2 or 3-3-3 or 3-4-3. At 18in 11-abreast, that's as wide as standard economy gets. If you want more, go for premium econ or business class.
What is the drawback of having a dual wing layout like a traditional Biplane?
If wing length is the issue, then why not put half the wing directly on top of the other half, possibly joining the two wingtips to reduce the vortex effects?
If wing length is the issue, then why not put half the wing directly on top of the other half, possibly joining the two wingtips to reduce the vortex effects?
An "enclosed" wing tip doesn't eliminate the vortices, it just moves them to different locations - the drag remains the same. Again, a common fallacy not supported by data or analysis.
PDR
Last edited by PDR1; 20th Feb 2016 at 22:37.
I did a simple wingflex model to see how the wing would flex.
PDR
I REALLY SHOULDN'T BE HERE
Pretty tricky to service those engines way up there and you would need some pretty tall de-icing trucks too. Lots of logistical challenges, probably all of which would be surmountable with enough investment but at the end of the day would it be economical to have bespoke equipment? What happens if you divert to somewhere without the bespoke support?
