How Does a Missile Stay Upright During Liftoff?

AI Thread Summary
A missile's stability during liftoff is primarily influenced by its high center of gravity and small base, making it susceptible to tilting. Early NASA launches experienced significant failures due to this design flaw, with nearly half resulting in catastrophic tilts. Single-engine missiles face more challenges in maintaining balance compared to multi-engine designs, which can adjust thrust to counteract tilts. The initial moments after launch are critical, as the missile's upward momentum increases stability as it ascends. Understanding rocket stability can be enhanced by consulting resources like NASA's website for detailed explanations.
Jozsef
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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
 
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Jozsef said:
its massive upward linear momentum will further help in stabilizing its flight path
What do you mean here? Angular acceleration due to an unbalanced torque, doesn't depend on linear momentum.
 
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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