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As another answer said, Drag is less than lift because aerospace engineers are generally competent at their jobs and so they design the shape of aircraft such that $C_l>C_d$ The main feature which achieves this is to have an airfoil which is longer than it is thick. Pressure differences $\rho$ above and below then have a lot more area $A$ to work on than ...


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Think of the wing as like a wheel. If it had no friction it would have no drag at all. It has some drag which dissipates energy, but if it is really long and skinny like this <======================> it has arbitrarily low drag. That's because the main cause of energy loss is in the wake vortices that form at the tips of the wing. If the amount of weight ...


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The first important thing to note is that drag an lift are orthogonal to each other. The lift pulls the plane up and the drag pulls against the direction of the flight. So at first glance those forces are independant of each other and as long as the lift is higher than the down force by gravitation, the plane will stay up no matter what the drag does. That ...


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I find it helpful to think of another famous problem. You are carrying a large stone with a mass of 100kg. You walk 100m with it. How much work did you do to the stone? The answer, of course, is none at all. The force you applied to hold the stone up is perpendicular to the movement, which means no work is done. This, of course, is counter to our ...


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The two formulas are almost the same, so why is drag less than lift? Drag is less than lift because aerospace engineers are generally competent at their jobs and so they design the shape of aircraft such that $C_l>C_d$ Not all shapes have that property. That is why aircraft don’t have random shapes. Their shapes are designed expressly to minimize drag ...


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