216 views

For jetliners, how is a swept wing justified over a thin wing?

For a given speed, a swept wing is a fatter alternative to a straight, thin wing. But why? Does not the sweep lengthen the wing and make it heavier? Is the swept wing chosen for the extra fuel tank ...
207 views

Explained intuitively, why does aspect ratio affect induced drag?

Over the last few hours, I've been trying to intuitively understand induced drag, and how aspect ratio affects it. I already know the equations, but while they explain the relationship, they do not ...
102 views

How do you calculate the optimal cruising speed of an airfoil?

I am working on a school project (aircraft design). I would like to know how to calculate the cruising speed of a given airfoil. For example, if I have a NACA 5613-35 airfoil (that is the NACA 4 digit ...
156 views

First, let's assume that problems with approach/TO speeds can be fixed by high-lift devices. Here we read that the wings create more drag than the fuselage. So, an improvement seems obvious; shrink ...
227 views

Why should I not use a “lifting tail” on my ultralight design?

In my misspent youth I designed and built many rubber, gas, and RC models. When I wanted good climb and glide I used a aft CG [60 to 80%] and a lifting tail. I had no stability or control problems, ...
187 views

Relationship between wing aspect ratio and speed [duplicate]

For some reason, I cannot find a relatively straightforward source online which discusses the relationship of wing aspect ratio and how it affects speeds of an aircraft. Specifically, is there a ...
284 views

How can a designer maximize the glide ratio of an aircraft with low aspect ratio wings, other than by increasing the aspect ratio?

As I understand it, the gliding range is given by a lift to drag ratio—hence to increase the gliding range, I would want to increase the lift and reduce the drag as much as possible. To that end, ...
31 views

Will wingtip drag always be more for a smaller aircraft, keeping constant aspect ratio? [duplicate]

Sometime ago, I came across an article (I couldn't find it) which stated that wingtip drag was only related to absolute wingspan. That is, for the same wingspan and lift force, varying the chord will ...
612 views

Elliptical wing planform and elliptical lift distribution

I know that there are similar topics already here, but after reading them I still do not understand everything. From what I know elliptical lift distribution gives the least amount of induced drag. ...
178 views

Is there a rule of thumb for aircraft design? [duplicate]

I'm wondering how to best scratch build an rc aircraft and what rough proportions the aircraft should be in. I'm aware of the fineness ratio that determines the width to length ratio of a cross ...
532 views

Why don't solar powered aircraft use wings with more surface area

I was looking at some solar aviation projects, and I noticed they appear to follow the designs of a glider. The Helios drone above is basically a flying wing with a high aspect ratio. And the solar ...
36 views

Wing Shape: Long/Wide Span Wings vs Deep Wings [duplicate]

Planes use wings to generate lift. The wider the span of the wing (looking at the plane from the front) the more lift it generates, however, this is at the expense of more drag. Some planes like the ...
1k views

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 ...