Comment Re:Darwin at work? (Score 2) 349
I agree with the reason that the nozzles are put below the tanks to keep them from exploding from the hot flaming exhaust, but I disagree with the optimum place for the nozzles.
The optimum place is above the center preferrably at the top of the entire rocket, atleast until you get to space. While in the Earth's gravity and flying into space, the best place is the top of teh rocket. This is because that gravity helps stablize the rocket.
The acceleration due to gravity is the same on all parts of the rocket (as said by WolfWithoutAClause), but the force can be applied at the center of mass/center of gravity. By putting nozzles on top of the rocket above the center of gravity, stability is increased. As far as the thrust vector and center of mass being misaligned that doesn't matter. As long as there is a thrust vector on each side of the nose. This would cancel out the lateral thrust of each of the rockets and leave on the vertical thrust. The only thing that would have to be worried about is that the thrust vectors' lateral components were not canceled by the other. This could then be corrected by having a throttle control on the amout of fuel fed through the nozzles.
So yes, gravity helps stability when the nozzles are above the center of gravity. The Force from gravity would create a moment force about the propulsion unit and would continue to create this moment force about the unit until the center of mass/gravity was inline with the propulsion unit and straight down to earth.
If you do not believe me look it up in a Physics book, or a Mechanics book, or any other college book that is about Vector Forces.
The optimum place is above the center preferrably at the top of the entire rocket, atleast until you get to space. While in the Earth's gravity and flying into space, the best place is the top of teh rocket. This is because that gravity helps stablize the rocket.
The acceleration due to gravity is the same on all parts of the rocket (as said by WolfWithoutAClause), but the force can be applied at the center of mass/center of gravity. By putting nozzles on top of the rocket above the center of gravity, stability is increased. As far as the thrust vector and center of mass being misaligned that doesn't matter. As long as there is a thrust vector on each side of the nose. This would cancel out the lateral thrust of each of the rockets and leave on the vertical thrust. The only thing that would have to be worried about is that the thrust vectors' lateral components were not canceled by the other. This could then be corrected by having a throttle control on the amout of fuel fed through the nozzles.
So yes, gravity helps stability when the nozzles are above the center of gravity. The Force from gravity would create a moment force about the propulsion unit and would continue to create this moment force about the unit until the center of mass/gravity was inline with the propulsion unit and straight down to earth.
If you do not believe me look it up in a Physics book, or a Mechanics book, or any other college book that is about Vector Forces.
