Linked Questions

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194 views

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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0answers
27 views

Would wing fences or chord wise corrugated tape increase the efficiency of a short span wing? [duplicate]

This question is not a duplicate ... Would wing fences or chord wise corrugated tape increase the efficiency of a short span wing? I understand that larger span wings have less % span wise flow. ...
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9answers
10k views

How complete is our understanding of lift?

I'm currently studying for my PPL and one of the accepted textbooks contains the following disclaimer at the end of the Principles of Flight section on lift: It is important to note that the ...
39
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3answers
10k views

How does an aircraft form wake turbulence?

This question discusses how wake turbulence can affect planes flying in formation. It got me wondering, how do aircraft (the wings in particular) form wake turbulence to begin with? It can't be as ...
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3answers
9k views

What is the lift force per unit span?

I got Aircraft Design: A conceptual approach for Christmas, and I'm having a hard time with lift coefficients because I honestly have no idea what "lift force per unit span" means, so can someone ...
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3answers
2k views

Is induced drag essentially nothing more than a specific type of form drag?

If I were standing outside on a windy day holding a flat rectangular object such as a food tray up in the wind, orthogonal to the direction of flow, the drag created would be classified, mostly, as ...
4
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3answers
14k views

How does the aspect ratio of a wing impact its lift?

The wing lift formula shows that lift of a wing is proportional to its area. $ L = {\dfrac 1 2 \times \rho V^2 \color{magenta}S C_L} {\small \begin{align} &{} &&\text{where:} &&L =...
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2answers
6k views

How do Hoerner Wingtips work?

I was just reading up about different methods of reducing drag through the different wingtip designs when I come across Hoerner Wingtips. So after some research, I have two questions. According to ...
12
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2answers
4k views

How is the induced drag calculated for a wing with elliptical planform?

How is the induced drag calculated for a wing with elliptical planform ? Is this wing shape the most efficient ?
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3answers
3k views

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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3answers
3k views

Is the low air pressure on top of the wing the major contributor to lift?

I am kind of old time flyer. Started to fly with those primitive hang-glides with titanium frame and the yoke control, around 1966 and then after a few close calls and getting older I switched to ...
8
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4answers
1k views

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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3answers
2k views

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. ...
4
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1answer
594 views

Where does upward momentum come from in leading edge vortex?

I believe I am beginning to understand how a leading edge vortex creates lift. Faster air creates a lower pressure above the wing making lift. But I am hoping to get another view of this in terms of ...
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1answer
3k views

How can I calculate effective wingspan of a high aspect ratio model airplane?

I've heard of people talking of wingspan and effective wingspan. Considering: L = Lift Coefficient . 1/2 Rho . Velocity ^ 2 . Surface Area, I understand that tip ...

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