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### How to distinguish the induced drag of a lift-producing wing from its pressure drag?

Quote John Anderson Fundamentals of Aerodynamics: "The three-dimensional ﬂow simply alters the pressure distribution on the ﬁnite wingin such a fashion that a net pressure imbalance exists in the ...
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### Why do most authors use wingtips vortices as reason for 3D flow around wing?

Quote John Anderson Fundamentals of Aerodynamics: The three-dimensional ﬂow induced by the wing-tip vortices shown in Figures 5.4 and 5.5 simply alters the pressure distribution on the ﬁnite wingin ...
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### How pressure fields change around wing?

In the 3D case,downward turning is immediately above and below the wing is stronger than in 2D case,for the same lift.This is because more rapid dying off the pressure above and below the airfoil ...
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### How can the 777X's longer wing reduce vortices? [duplicate]

I saw the following on this web page: The purpose of the longer wing is to reduce drag caused by vortices, or wake turbulence, that form at an aircraft's wing tips. The less drag, the greater the ...
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### Why do wall-to-wall airfoils in wind tunnels produce no (or infinitesimal) downwash?

There are several induced drag explanations out there saying that tip/wake vortices “come from” downwash and downwash “comes from” lift. I’m using quotes because the concept is that there are no cause ...
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### What can a new student pilot do on their own to prepare for class and instruction?

What is the best way to start for beginners learning to fly? I have a class set up and a instructor but not for another week or two. I just want to know if there is anything extra that I can start now,...
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### How is drag created from wingtip vortices?

What is the reason for the drag due to wingtip vortices? This question is about (general) performance, but doesn't answer the drag aspect.
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### How does the extension of inboard flaps raise the effective critical angle of attack of the outer wing?

I raised a question about this on this post in the comment section and was suggested by Peter Kämpf to create a new question. So here it goes: How does the extension of inboard flaps raise the ...
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### Can this design provide more lift force than thrust from engine?

The problem is depicted in the picture: Generally, why we don't use engine blow wings to fly? Can we use wind-tunnel-like wing to generate lift force? Can it generate more lift than thrust? If it ...
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### Is induced drag caused because of the tilt of the wing backwards?

In this question: Why is induced drag less on a high span wing? In the answer it was stated that wing tip vortices do not cause induced drag. If this is the case then what causes the induced drag. ...
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### When leaving ground effect, why is there a nose-up change in moment?

The Airplane Flight Handbook states: The aircraft leaving ground effect will Require an increase in AOA to maintain the same CL Experience an increase in induced drag and thrust required ...
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### Is induced drag not caused by tip vortices?

According to most online resources, including NASA, induced drag is caused by wingtip vortices which induce downwash. However, in StackExchange I have found a few answers (Peter's and Jan's) that ...
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### Why does the elliptical wing have the lowest drag?

I read that the elliptical wing has the lowest induced drag. Why is that so? I welcome a mathematical and intuitive explanation.