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0 pointsbb6119y ago0 comments

That's a pretty poor approximation, and I think the result discounts the meaning of the original point.

The A380 is a lot more like 3 boxes (based on A380-800: http://www.airbus.com/fileadmin/media_gallery/files/tech_dat...):

1) A fueselage box with a cross section of 2067 ft^2

2) A wing box of ~1200 ft^2 (a very broad approximation because of engines, the actual wing box - the part of the plane where the wings meet the fueselage - and the curve of the wings),

3) A tail box with a cross section of 144 ft^2

So a total cross section of ~3411 ft^3 * 827 fps = ~3 million ft^3

Point being, the plane isn't moving 11 million cubic feet just to move forward, it pushes on a little more than a quarter of that directly. These wake effects happen because it's disrupting so much air outside of the zone it actually travels in, mostly below and behind it.

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Dylan168079y ago

> That's a pretty poor approximation

It's not an approximation. I'm giving a sense of scale, not saying how much volume the plane has. The point is that while 11 million cubic feet sounds like a lot, if you put it in a big box next to the plane then they would be on the same scale.

> the plane isn't moving 11 million cubic feet just to move forward, it pushes on a little more than a quarter of that directly

That's jseip's post's problem, not mine.

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