Linked Questions

10
votes
1answer
965 views

Why are vortices produced at wingtips a source of drag, while vortices from the leading edge (harnessed by delta wings) good?

From my understanding, wingtip vortices produce a downward force on the aircraft, effectively increasing drag. Meanwhile, when considering leading-edge vortices on delta wings, we only consider the ...
6
votes
3answers
2k views

Can gliders and single-engine planes have vortices?

I read, A third physical explanation of the source of induced drag is that the wing tip vortices contain a certain amount of rotational kinetic energy. This energy has to come from somewhere; indeed, ...
36
votes
4answers
35k views

What do winglets do to increase aircraft performance?

It seems like a lot of the newer airliners have winglets or wing fences. How do they improve aircraft performance?
60
votes
11answers
38k views

How do wings generate lift?

Just the basic question that every aviation enthusiast must be curious about: exactly how does a wing generate lift?
9
votes
3answers
3k 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 ...
38
votes
3answers
11k 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 ...
8
votes
5answers
24k views

What is profile drag?

I know about induced drag, parasite drag, form drag, skin drag, wave drag, and interference drag. But I don't encounter the term profile drag often, and I can't find a good definition of it. Is ...
57
votes
5answers
13k views

Is a winglet better than an equal span extension?

Is there indisputable evidence that a winglet improves performance over an equal span extension? Please note: I am only interested in L/D improvements. Winglets do improve roll performance, that is ...
11
votes
3answers
11k views

Does the downwash created by induced drag increase or decrease lift?

According to the theory I know, lift is produced by accelerating air downwards at the trailing edge (downwash). Hence, as downwash increases so does lift. Induced drag is due to vortices at the wing ...
4
votes
1answer
721 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 ...
6
votes
2answers
3k views

Why is induced drag less on a high span wing?

I have a basic question and sorry if it is a well known fact. I understand that the induced drag is due to the tip vortices changing the effective angle of attack (downwash). I searched some ...