Linked Questions

0 votes
1 answer

Lift without aerofoil?

I have seen some RC planes flying without any form of airfoil, the wing is literally a flat board. What I want to understand is how lift is generated under these conditions. I understand kinetic ...
FourierFlux's user avatar
1 vote
1 answer

Lift Coefficient question

I am making a RC Airplane, it has a wing profile as shown above. What might be the approx. lift coefficient of this? The wingspan is 80cm, what will the lift provided be by this wing at 65kmph ?
S.A's user avatar
  • 43
7 votes
2 answers

Why does a flat plate create less lift than an airfoil at the same AoA?

This picture of the lift curve slopes for four-digit NACA airfoils and a flat plate is from another question on this topic. It shows that at the same positive AoA, a flat plate generates less lift ...
Frank's user avatar
  • 415
0 votes
0 answers

How to approximate the drag for rectangular vertical flat panel placed along the wind and inclined?

So on the top is the view from the top, below it is the side view. If the angle is zero it is similar to simple flat airfoil. So I calculated the Cl and Cd in xfoil and got the Cl = 0 and Cd = 0.02398 ...
Aleksey's user avatar
2 votes
1 answer

How to calculate drag of a flat rectangular surface at given area, air density, airspeed and angle of attack?

I'm a complete noob in aerodynamics, and I'm trying to calculate the drag of a rectangular flat area, given the air pressure / density, area, angle of attack and airspeed. I've read this question, but ...
TheEagle's user avatar
  • 1,394
9 votes
1 answer

Why are there two local maximums on some CL vs AOA curves?

I know what a stall is but I don't understand why there are in some cases two local maximums on the $C_L$ vs AOA curve of some airfoils. What is the reason for the mini stall that occurs before the ...
user217340's user avatar
4 votes
3 answers

Why does stalling increase drag?

I understand (I think) why lift reduces in a stall. What I don't understand is why drag increases. I can see that the ratio of drag to lift would increase, but I'm not sure I understand the mechanism ...
jfowkes's user avatar
  • 169
3 votes
1 answer

What would be the power requirements and performance of a Scroggs-type delta-wing aircraft with a 250 cm span?

Roy Scroggs, a tailor, patented in 1917, US1250033, and in 1932 US1848578, a Delta Wing plan form machine 'Flying Dart', flight tested with an OX-5 engine, they say ...
Urquiola's user avatar
  • 1,631
2 votes
4 answers

What is formula for induced drag in stalling regime?

I'm wondering what is the formula for induced drag in a stalled regime, i.e. in a regime where the $C_L$ (coef. of. lift) has started to decrease but is still nonzero. I've a feeling that the ...
agronskiy's user avatar
  • 223
5 votes
1 answer

Is it possible to maintain horizontal flight with the angle of attack above critical value by increasing speed?

In this video a stall happens at 1:40 upon reaching the critical angle of attack. The air flow is now detached from the upper part of the wing, resulting in higher pressure above the upper part of the ...
Electric Pilot's user avatar
2 votes
2 answers

Is the angle of attack equal to zero when the plane is on the ground with wings level?

I read in the internet that when an airplane stands at the airport (horizontal) it has zero degree aoa. The captain must pitch up the plane during cruise to generate an amount of lift and when the ...
D. Frederico's user avatar
3 votes
1 answer

How do symmetrical airfoils generate lift? [duplicate]

It is widely understood that the curved shape of a typical airfoil (such as a Clark Y) causes a pressure difference that creates lift. How do symmetrical airfoils do this when the top and lower ...
Madhav Sudarshan's user avatar
2 votes
0 answers

Why aren't compressor and turbine blades flat? [duplicate]

Why are the compressor and turbine blades of a jet engine shaped as airfoils? Why can't they be flat?
Manfred VonRichtoffen's user avatar
11 votes
2 answers

How would an airfoil react if it was flown backwards?

Out of curiosity what would happen? Would pressure on both top and bottom flip? or stay the same or act as a normal wing with less lift? I'd assume it would still take longer to travel over the top ...
ApolloMission4's user avatar
13 votes
2 answers

What is the method to calculate a finite wing's lift from its sectional airfoil shape?

I am struggling to get my head around a concept that I believe should be fairly simple to understand. Lift versus drag and AoA data of many airfoils are freely available, for instance the NACA 4-...
Jonny's user avatar
  • 2,038