# Tag Info

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I'm not sure what you mean by 'payload capacity'. Airplanes have what's termed a 'useful load' which is the maximum combined weight of the passengers, baggage and cargo, and useable fuel. If you wanted to increase useful load, you would have to make the airframe and all systems aboard the airplane which constitute useful load lighter. This does have the ...

1

Yes, it is possible and variable-incidence wings have been used. The only production example was the Vought F-8 Crusader, used primarily by the US Navy. It had a variable-incidence wing, which tilted nose-up by about 7 degrees to give increased lift for takeoff. The conventional solution of a lengthened nose undercarriage was deemed impractical for the ...

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All it means is the deck angle of the fuselage will be lower for a given speed. Weight being the same, the wing will fly at the AOA it needs to fly at to support the weight. By increasing the incidence, the fuse will just be pointing down more because AOA will be the same for a given flight condition. You have a downstream problem as well because the ...

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In short, no. But it depends... Angle of incidence does not increase or decrease lift, only angle of attack and airspeed affect lift. Let me explain - If you had an aircraft with a variable angle of incidence you could fly at a constant angle of attack while varying the incidence and have no effect on lift. Picture the wing steady with respect to the ...

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If I am thinking about this correctly, increasing angle of incidence would increase lift because you would also be increasing angle of attack. Increasing the angle of attack would increase lift until you reach the critical angle where you have airflow separation and aerodynamically stall the wing. It’s the angle of attack that’s important. A better ...

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Yes. Angle of Attack is included in the Lift formula. Lift generally increases with angle of attack in a linear fashion until AOA reaches stall. This is why it is not a good idea to fly at too high an AOA. Better to increase Velocity. Lift increases with Velocity squared. The Navy Vought F-8 Crusader had a "variable incidence wing" that was raised to a ...

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Thick, cambered airfoils such as the Gottingen, Clarke Y and Davis are the most efficient airfoils up to speeds where Mach number becomes critical. Lift is determined by the lift formula: $Lift$ = 1/2 × Coefficient of Lift × Air density × Wing Area × Velocity$^2$ Coefficient of Lift can be further broken down into Angle of Attack and Airfoil type. So ...

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This is true for most cases, because thin airfoils normally produce less drag and less lift than thick ones at the same angle of attack. But they are also exceptions. Thick airfoils, to be specific Supercritical airfoil, are commonly used by commercial airliners, but not only because they could produce less drag. Airlinears fly at speed which shock wave ...

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Helicopters in general use asymmetric aerofoils because they are not required to fly inverted or produce negative lift. Intermeshing helicopters are no different in this regard. The exception would be aerobatic model helicopters, which use symmetrical aerofoils because they are designed for similar performance either way up.

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What is the $(t)$ in $\bar{y}_n^{(t)}$ in (A-2) The text doesn't say. t in German normally denotes chord (Tiefe), but since we later see $\bar{y}_n^{(s)}$ for the camber line (Skelettlinie), it here stands for Tropfen, denoting the thickness distribution of the uncambered airfoil. I would also interpret the long dash between $\bar{y}_n^{(t)}$ and the sum ...

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FX stands for Franz Xaver, Professor Wortmann's given names. The next two digits stand for the year this airfoil has been designed. Add '19' in front and you have the full year. Then may follow one or two optional letters which specify a dedicated use, but they can be missing for general purpose airfoils. For example, the 'L' in FX 71-L-150/30 stands for "...

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It would depend on the Angle Of Attack of the area of the wing in the propeller slipstream. If the flow was at the wing's zero-lift AOA, there would be no lateral force. Aerobatic aircraft with symmetrical airfoils that are at zero incidence in the propeller slipstream would be that case. Wayne Handley's Turbo Raven hovering act back in the 90s, where he ...

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A practical example of your question is when a model aerobatic aircraft with a conventional aerofoil profile (ie, not symmetrical) is fitted with a sufficiently powerful motor that it can be made to hover in the vertical position. This is quite a common trick. The answer is yes, there is a force in the direction of the red arrow. The model might drift in ...

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Yes, that wing would create some sideways lift. Whether it would actually move depends on how you are holding your aeroplane vertical. Obviously it's not going to move if you've bolted it to a big, heavy, test stand. For an aerobatic plane prop-hanging, it would depend whether the aerofoil is symmetrical, and the angle at which it is fixed to the plane. The ...

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From Mason’s Perspective on the X-29: The other issue with this airfoil is that every Grumman aerodynamicist felt the need to “improve” it, so that there were many variations. I think the airfoil that was used on the X-29 was known as K-Mod 2. I’m not sure anybody can say with certainty what the actual airfoil coordinates are. Grumman was not good with ...

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What is the important parameter in foils that will make it start spinning The aerofoil needs to create lift in a direction that causes rotation. Typically aerofoils stall at around 15 degrees angle of attack, so you would need to rotate your blades to around -75 degrees to get them started, and gradually reduce this as they speed up. and descent with ...

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There's some info on autorotation, including some references, in this answer. And also a pertinent question on Physics SE. Free body diagrams included. In short: Autorotation only works in a satisfactory way if the vehicle has forward velocity: in a vertical descent, in optimal circumstances, autorotation works as well as a leaky parachute does. Getting ...

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First I have to say that XFOIL is not the right tool for such a high Mach number. Professor Drela has written ISES to address the shortcomings of XFOIL at transsonic speed. Next, the critical Mach number is well defined as c_{p_{crit}} = \frac{2}{\gamma\cdot Ma_{\infty}^2}\cdot\left(\left(\frac{2}{\gamma+1} + \frac{\gamma-1}{\gamma+1}\cdot Ma_{\infty}^2\...

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It sounds like you're looking for a Supercritical section, so this NASA report on Supercritical Airfoils may be of use.

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The subtitle of the video states: This video shows a high-fidelity CFD simulation of flow control applied to realistic wing profiles using PHASTA and ParaView Catalyst. Work done by Michel Rasquin from Argonne and Ken Jansen from UC Boulder. Realistic wing profiles sounds like: we're actually looking at a wing in a vertical orientation - or in a ...

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