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Mechanics of a missile liftoff

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  1. Aug 24, 2014 #1
    From a "design" viewpoint, a missile (see: Saturn V) has a very high center of gravity and a very small base.
    It can therefore be expected that the least disruption of the location of the center of gravity relative to the base, will result in the missile to tilt and fall over, especially in the very first seconds after launch.
    Indeed, in the early days of the NASA program, almost 50% of the test launches resulted in a catastrophic tilt.
    I can find no better comparison for my lack of insight than keeping a broom stick upright and in balance on your palm. This is not easy.
    In my mind, this problem is more pronounced for single engine missiles than for multi engine missiles because it can be expected that differential control of the thrust from the multi engines could compensate for a beginning tilt. But then, I presume that the corrective directional forces must be tremendous, given the height and the mass of the missile.
    I think to understand that after launch, when the missile has already build up a high vertical speed, its massive upward linear momentum will further help in stabilizing its flight path, with less corrections needed. My problem to understand "mechanically" a successful launch, is indeed in the very first seconds after liftoff.
    Can someone help me for a better understanding? Many thanks, respectfully, Jozsef
     
  2. jcsd
  3. Aug 24, 2014 #2

    A.T.

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    What do you mean here? Angular acceleration due to an unbalanced torque, doesn't depend on linear momentum.
     
  4. Aug 24, 2014 #3
    Use a well-known search engine to look for "rocket stability". The first link probably takes you to the NASA site which has all the information you want.
     
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