Wing design question

SixPapaCharlie

SixPapaCharlie

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Looking at planes, I see variety of wings and I am curious as to what the differences are.

Lets say I start with a plane where the body, power, and tailfins remain unchanged.

1. Both have identical wings with the exception of 1 having a thin (flatter) wing and the other having a fat wing (Speaking of top to bottom here)

What would I expect to be different in the flatter versus fatter wing


2. Both have identical wings with the exception of 1 having a longer chord (LE to TE) and the other having a narrow wing (Speaking of front to back)

What would I expect to be different in the longer chord versus narrow wing

Foundation for this question is I say this experimental low wing where the wing was just really fat (top to bottom) and I was wondering what that did for flying characteristics.

Also at our field we have these cargo planes (twin high wing) that are very square w/ huge bodies relative to their very thin (front to back) wings.
 
Here ya go. Look at that tiny wing.

SD330_N52DD.jpg
 
The thicker the wing, the better low speed characteristics. Good, slow speed airfoils don't do well at fast speed, and vice versa.

Have a look at the picture on this wiki page.

https://en.wikipedia.org/wiki/Airfoil
 
Lots of things at play, but basically the thicker the wing, the less speed and more lift it will generate for a given amount of power pulling/pushing it through the air. The thicker wing will pick up more weight/hp while the thinner wing will have a higher speed. Chord length vs Wing span is also known as aspect ratio, and the effects are similar, a long wing with a short chord is known as a high aspect ratio, and while more efficient at low speed, also has a lower top speed.
 
SixPapaCharlie said:
Here ya go. Look at that tiny wing.

SD330_N52DD.jpg
Click to expand...

That's a Shorts 3-30. I'm told the fuselage of that aircraft actually provides quite a bit of lift as well as the wing. Also, all of the fuel is stored in the upper fuselage, so the
wing doesn't need internal space for fuel tanks.
 
Been reading Ecbar's book on flying the bonanza and he has a graph comparing the stall characteristics of a Cherokee wing and the bonanza wing. Performance wise, the bonanza wing is much more efficient with less drag. Stall wise, let's just say the bonanza wing let's go all at once in a stall (assuming no vortex generators). The Cherokee just bobbles around near the stall..


Interesting stuff....
 
Longer chord (front to back) usually means higher drag and better low speed characteristics. Higher aspect ratios like that Shorts you pictured tend to have less drag which can allow more speed for the power used. Also helps with higher altitude flight. Think gliders/sailplanes. As others noted there is a lot more to all of this and one thing is wing stiffness. The thicker wing will be stiffer for a given weight so the thin wing needs more material to attain the same stiffness. This adds weight. It is quite visible on large transport aircraft as the wings flex. On the Shorts you pictured you might note that it has struts to help with this issue. The thin wing by itself wouldn't have enough stiffness or strength to be cantilevered. Helps the fuselage too as it spreads the concentration of the load out.

Frank
 
Check out the video below @3:45...there are several minutes of footage of an advanced flight control system taking advantage of both fat (high) and thin (low) camber wings. Notice how the leading edge flaps "dig" almost 40 degrees down at slower speeds (or when more lift is desired/required), then return to neutral as the plane accelerates.

https://youtu.be/nw0gjw1XIIk
 
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As some have said, a thicker airfoil will typically provide more lift at a given speed.

A higher aspect ratio is more efficient, especially at higher CL's, as induced drag decreases with higher aspect ratio (this assumes the wing area is the same). Long wings are more difficult to design, can create maneuvering issues (think glider), and can add drag at high speed due to more surface area per wing area.

A thicker airfoil also has the structural advantage of allowing a thicker spar, which may allow it to be cantilever. Some thin airfoils, like the one shown, need external bracing with a strut. This is changing with composites though and even in some metal planes. Take a look at Lancair and Cirrus. Relatively thin composite cantilever airfoils.
 
Best example would be Piper 180/Archer.
The older PA-28-180 Cherokee had a Hershy bar fat wing. The newer PA-28-181 Archer had a thinner wing. Same with the PA-28-235 and the PA-28-236 Dakota. I don't have the numbers here, but check the differences in climb and cruise for the same HP.
 
BillTIZ said:
Best example would be Piper 180/Archer.
The older PA-28-180 Cherokee had a Hershy bar fat wing. The newer PA-28-181 Archer had a thinner wing. Same with the PA-28-235 and the PA-28-236 Dakota. I don't have the numbers here, but check the differences in climb and cruise for the same HP.
Click to expand...

:lol: Not a good example since the later, thinner, taper wings lose speed.
 
Clark1961 said:
not a good example 'cause they are the same airfoil...
Click to expand...
True, though the (semi-)tapered wings have a leading-edge droop that gets progressively greater from the start of the taper out toward the tip.

It's a NACA 65(2)-415; outboard leading edge incorporates modification No. 5 of NACA TN 2228.

The tapered wings are the same as the Hershey-bar wings out to the outboard ends of the flaps, then taper proportionately in chord and thickness.
 
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