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well you see the lift has got to do with the mass. Because of the design of the wings of the airplane the speed of wind going above the wing is more than the speed of air going from the bottom of the wing. Therefore from the Bernoulli's equation the pressure above the wing is less than the pressure below the wing. this pressure difference causes the lift. ...


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It is true that the heavier plane needs a greater lift and this is seen in practice. If two planes at equal altitude loose power at the same time and one weighs more than the other they will be able to glide the ...... same distance! One of them descends faster than the other but it glides forward faster to generates more lift. It seems odd, but one ...


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F = MA. The force required to lift a plane is mass times acceleration. Acceleration on earth is around 9.8m/s/s. The mass increase will therefore increase the amount of force it's applying, and therefore the force required to cancel it out. Two balls of the same shape but one has more mass, it will fall at the same speed as the other, but will press harder ...


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The answers I've seen above accept your premise: the plane would indeed fly off-Earth if it was "dumb" (i.e. altitude not controlled by human or software). This is not the case. This is my attempt to explain as simply as you are reasoning: Assume a "dumb" plane flights straight, parallel to the current position. Nothing turbines pumping and there is no ...


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If I'm flying parallel to the ground and I never adjust my attitude, shouldn't my altitude above the ground start rising if the Earth is curving away from me? This question, and most of the responses and comments to it, are based on a misunderstanding of what "straight and level flight" means. It does not mean flying in a Euclidean straight line at a ...


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I am a student pilot. I've got 100 hours and 300 landings. Throw a paper airplane. Does it fly in a straight line? Of course not. Neither does a big plane. It only follows the course, horizontally and vertically, that the pilot controls it to fly. The way it turns from one heading to another is by temporarily banking to one side, exactly like a bicycle. ...


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I'm no pilot, but I believe that airplanes typically (whether on autopilot or not) maintain a constant altitude when cruising, i.e. height above the ground, using an altimeter. So if the plane (via computer or human operator) detects the altitude is increasing, the plane uses its control surfaces to alter its ascent rate and go back to the desired altitude. ...


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In practice, this is exactly what would happen if you were to fly in a straight line. This is why planes don't fly in a straight line: they adjust their path to stay at the same altitude.


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Lift is approximately proportional to velocity squared of the aircraft, not the thrust. That is why runways are required. So the thrust is used the accelerate the aircraft to take-off velocity, which will produce enough lift to overcome gravity. Also, the fact that the thrust is less than the gravity in Antonov implies that it can't do this: ...


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From when I worked among missile engineers, accelerometers were used, along with gyroscopes (mechanical or laser). I don't know of 6th order differential equations. I do know of 3rd order, namely in the steering by swiveling the engine nozzle. Specifically, the engine nozzle angle is off-center by a certain amount, causing an angular acceleration (2nd ...


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All materials have a resonant frequency Well, sort of. In general, complicated structures will have many resonant frequencies where the amplitudes of any oscillations will have local maxima. However, one of the jobs of structural engineers, and I would assume this would apply to aeroplanes too, is to find these frequencies and make sure that either (a) ...


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You say: All materials have a resonant frequency but this is at best an oversimplification. Any system has a set of normal modes and if you apply driving force at a frequency that matches a normal mode then you will get a resonance. However for any system significantly more complicated than a tuning fork there are many normal modes and non-linearities ...


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Multi-variable model-predictive process control technology has been around for some time now (at least since the mid 1980's). This means that the number of variables in the control problem is not an insurmountable problem. Assuming that the SpaceX process control engineers have a good intuitive understanding of the theoretical aspects of landing their ...



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