Linked Questions
31 questions linked to/from How does chord length affect wing design?
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What is the Relation between Critical AoA with Chordline? [duplicate]
I read here an explanation about angle of attack (AoA) as below:
Overly long (forward-back wise) wings will generally have a smaller critical Angle of Attack while smaller ones will have more ...
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57
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6
answers
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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 ...
- 225k
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4
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5k
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Why are heavy flaps better than just a bigger wing?
Flaps increase lift during landing and T/O. But when retracted, they do nothing. The space needed to stow the common fowler flaps can't be used for anything else - fuel or structure. Extended flaps ...
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3
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Why are fighter jets so loud when doing slow flight?
Going to air shows I noticed that when fighter jets did slow fight, it was just as loud as high speed passes. Why is this?
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What is the purpose of a dorsal fin such as on the Boeing 737?
I've noticed that the 737 has a rather unusual vertical stabilizer, with an extension at the front. Is the 737 the only plane equipped with such a vertical stabilizer, and what is its purpose?
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21
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3
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What dictates the aspect ratio of an aircraft's wing?
When designing an aircraft, there has to be a decision as to the aspect ratio of a wing. It's been said that having a higher aspect wing will reduce drag for the same wing area, however most of the ...
- 10.4k
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2
answers
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Why do some airplanes have vertical strakes?
A lot of different aircraft have vertical or near-vertical fins below the empennage, or above the empennage and attached to the front of the vertical stabilizer.
What purpose do these devices serve?
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15
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3
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What are the disadvantages of a delta wing biplane design?
The idea of a delta wing as I understand it is to reduce stress on the wing and drag on the leading edge. Now using two delta wings on separate planes, on one frame would presumably allow for a ...
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16
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3
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How would an Inverted Delta Wing planform behave, Straight part forward? Are there wings shaped this way?
There is info about straight edge wings, swept back wings, swept forward wings, delta wings.
Is there also info about a Delta wing with a straight leading edge and a tapered trailing edge, the point ...
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14
votes
3
answers
3k
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Do some light sport aircraft have clipped wings to lower their cruise speed?
Light sport aircraft may have a max airspeed in level flight at MCP of 120kts. I have heard that there are some light sport aircraft that have had their wings clipped in order to have a lower cruise ...
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3
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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 ...
- 731
4
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3
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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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12
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2
answers
3k
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What is the aerodynamic benefit of trailing edge sweep?
Sweep will allow flight at higher speed because the perpendicular air flow speed (over wing) is less.
But why is there trailing edge sweep?
We can have a swept leading edge and unswept trailing edge ...
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9
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5
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992
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Do most commercial jets have a negative lifting body?
I took a look at some example airfoils and noticed they all seem to have a downward hook at the end. I believe this draws the air downwards, creating a reaction force upwards: lift.
Now here is a ...
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5
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4
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What is the fundamental physics behind L/D decreasing as AoA increases beyond the optimal point?
Why does lift over drag decrease with AoA past the optimum AoA? Is it because the backwards vector for a given lift force on the wing is now larger for a given air particle compared to lower AoA?
...
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9
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1
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How can I calculate the rolling moment of an aileron for a given plane based on its performance?
Let's say I have an already-built airplane with known basic characteristics like weight, wing span and wing surface, and I can measure the time of all possible manoeuvres at different speeds.
How ...
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6
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2
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2k
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Is there a parameter that links the areas of the fuselage and control surfaces? [closed]
Do aircraft designers look at the ratio of how much fuselage surface area can be loaded onto a given unit of wing and tail surface area including elevator, aileron, rudder etc? (Possibly, the surfaces ...
- 1,015
5
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1
answer
13k
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What is the chord of a wing?
In the answer to this question the author mentions the chord of a wing. What exactly is that, and how is it used in wing design?
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3
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2
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2k
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Are high lift wings bad for faster speeds
I notice a trend in many aircraft designs. If the aircraft was designed to go slowly but have shorter takeoffs/landings they use airfoils with a high lift.
However for long endurance flights they use ...
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How do I achieve a lower stall speed, and capture potential CLmax without enough elevator control authority?
I am running some analysis on a uav, and the results I have found show that with proposed modifications I am unable to trim at my previous $c_{L\:max}$ and thus originally designed stall speed (...
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2
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5k
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How can we design a wing for cruising at very low speeds?
I was thinking about a simple super-light aircraft powered with a little low-power piston engine. Is there any way that we can design a wing so the aircraft flies very slow (like 25 km/h as minimum ...
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3
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How does aspect ratio affect the stalling angle of the wing?
I have been trying to find a clear answer for this but haven't been able to do so. From what I understand this is linked to induced drag but I'm not able to link it.
Could someone shed some light on ...
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1
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Does skin friction drag decrease with velocity?
The wings of subsonic planes have usually a very low surface area and aspect ratio as big as possible. However, in supersonic aircraft, wings with more wetted area (e.g delta wings) are used. Is this ...
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5
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1
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1k
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What's the theoretical background of the critical angle of attack?
The critical angle of attack seems to be at all (most?) airfoils around 15-20°. Why is that? Why is it in this range and not lower or higher? Is it just the result of optimizing airfoils? Or is it ...
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2
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2k
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How does wing aspect ratio influence lift and drag?
I know simmilar questions are all over the internet (and this website too), but there's one thing that i just cannot comprehend and none of the articles i read could explain it properly.
According to ...
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1
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Do wingtip vortices cause a decrease in the lift component of aerodynamic force, and do planes need to pull more AoA to compensate?
So, from what I know about wingtip vortices, they shift the angle of the relative airflow to where the effective angle of attack of the airfoil is lowered. Since the aerodynamic force is always ...
3
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2
answers
306
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Are larger airplanes more likely to stall?
Stalls happen when the boundary layer on top of a wing slows so much that it essentially becomes part of the airfoil.
My question is, as the wings on larger aircraft present a longer flow path for ...
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1
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How to proceed in designing a catapult glider with maximum flight distance? [closed]
As a basis for this question, take the following catapult glider:
http://www.guillow.com/spaceshuttle.aspx
This model has low aspect ratio wings, a thick wing section and a relatively wide fuselage, ...
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0
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1
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Is it better to reduce drag or increase lift?
Essentially my question is, in general is it better to have a lower drag or a larger lift. I know lift to drag ratios are used as an indicator but I think these don't give the best picture. For ...
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2
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1
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259
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What is the drag optimized wing form for given lift and bending moment?
I am trying to build a passive hydrofoil board.
Something like this:
I want to use wood and i am coming to the conclusion that i want to optimize drag for a given ...
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