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Well, both. Lift can be described as a moving wing colliding with air molecules at an angle, the result of the collision is the wing moves one way and the air mass the other, as per momentum physics. Moving the trailing edge, or the entire surface, increases the angle of attack, resulting in more lift at a given speed $V$: $Lift$ = 1/2 × Lift Coefficient ...


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Thankfully, aerodynamics in the usual flight range is linear. Therefore, there is a gradient of lift over angle of attack and another one over the flap deflection angle. Both are constant over a range of maybe ±15° and can be combined. The angle of attack is referenced to the fixed part of the flight surface and the deflection angle to the moving part ...


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A trailing-edge control surface, when it deflects, changes the camber of the overall airfoil. More camber means more lift, in whatever direction that airfoil is mounted. In your example, adding up elevator increases the horizontal stabilizer's camber, which increases the downward force it applies. Philosophically, "why" it does this is just, well, that's ...


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The top speed depends on the type of the airship. While the first designs were non-rigid, it became soon obvious that useable speeds could best be achieved with rigid designs because the higher dynamic pressure at higher speeds required more internal pressure to maintain the hull's shape. Given the low strength of early hull materials, the internal pressure ...


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The drag increases with the square of speed. Since thrust only slightly overcomes drag, doubling the thrust only results in a 40% increase of speed. In the case of a dirigible, doubling the thrust won’t double the speed. It will only increase the speed by 40%. There are other factors to account. Once the flow approaches transonic speeds meaning the speed ...


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Comparison of two giants from the golden age of airships LZ 127 Graf Zeppelin and LZ 129 Hindenburg provides some useful information on your proposed scaling. Both airships were around 800 feet long and cruised at 80 - 85 mph. Hindenburg was 35 feet wider, with more than double the lifting capacity, but required 4 x 1200 hp compared with 5 x 550 hp of the ...


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As for the weight vs. speed: a rigid or semirigid airship has a max takeoff weight, which depends on it's size (because the size pretty much determines the max lift). If this airship was to fly, say, only half of the max weight, it would not go any faster, as the drag would be the same because the size does not change. An airship may lift a load heavier ...


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I'll do this without most of the math since your target audience won't want to read equations in your story. In the simplest terms, the maximum speed of an airship occurs when the maximum thrust generated by its engines is equal to the drag it experiences while being pushed through the air at that speed. That drag depends on the diameter and length of the ...


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The lift is a force perpendicular on the cord of the wing. As a vector it points up and backwards, towards 11 o’clock. The horizontal component points towards 9 o‘clock and is called drag. The drag is cancelled by the thrust, a force pointing towards 3 o’clock. The vertical component of lift points towards 12 o’clock and cancels the weight (pointing at 6 o’...


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This is quite a flabbergasting question... As you're standing on the floor of your home, Lift equals Weight. The lift is supplied by the floorboards to your feet. That's static lift. If you tilt up a floorboard and pull a toy car across it, it will be lifted upwards and even fly up after the floorboard ends. That's dynamic lift. Note that the required ...


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In straight and level flight at an airspeed V, the weight W is balanced by the lift L, and the aerodynamic drag D is balanced by the thrust T. D is much smaller than L. In a passenger liner, D may be 1/12 ... 1/20 of the weight, or so...


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