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Both the airfoil shape and inherent properties of the air contribute to the stall angle of attack. You asked for a theoretical background, but I will list the factors that influence stall because there is no simple formula for it. The most important factor is the suction peak which develops right behind the stagnation point on the upper side of the leading ...


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This observation is only partially correct. If you take a generic, General aviation airfoils (moderately high Raynolds number; ie > 5 Million) this observation appears to be correct. Why is this correct? Because most GA airplanes Fly between a limited maximum speed and stall speed which correspond to lift coefficients say 0.01 to 1.5-2.00. CL is (...


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"What would happen if the thickness...are same throughout the wing". This is known as a "Hershey bar" wing, and is an excellent general purpose, easy to build wing for models and full scale aviation aircraft alike. Aircraft designers add twist or "washout" to wings to prevent the entire wing from stalling at once. Washout lowers the angle of attack of the ...


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If the airfoil profile does not change along the span, then we can expect the entire wing to enter a stall condition at the same time. This means the stall break will be sudden and sharp. If instead we transition between several different airfoil profiles along the span of the wing, we can get different portions of the wing to stall at different airspeeds/...


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In steady state flight Center of Pressure is at Center of Gravity. If center of gravity/pressure is ahead of aerodynamic center the aircraft will be staticly stable. Looking at it purely aerodynamicly, increasing speed will increase lift, pitching up and slowing the aircraft. The longitudinal stability nuetral point is at the aerodynamic center for ...


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For the pitching moment, two distinct cases need to be considered, the airfoil and the whole aircraft, both over a range of Angle of Attack (AoA). The questions centre around the main wing only, the picture in OP is of an entire aeroplane, creating some confusion. Airfoil. A positively cambered airfoil indeed contributes a nose-down pitching moment, as ...


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Reynolds Number is calculated as: velocity × chord/kinematic viscosity of air velocity is meters/second, chord is meters, kinematic viscosity of air is around $1.48 × 10^-5$ Then go to Airfoil Tools. As you make your selections, you can see, in the polar diagrams, the effect Reynolds number has on the lift and drag properties of your wing. A typical ...


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