A slightly asymmetric missile is a basically symmetric missile with a nonzero pitch moment at zero angle of attack. In flight this causes a trim angle that rotates with the missile and has a maximum when the spin is near resonance withe the missile's natural pitch frequency. A roll moment can be calculated, therefore the existence and stability conditions for equilibrium spin can be derived. The special case of the induced roll moment caused by a radial center of mass offset must be considered and a number of different types of possible equilibrium spin combinations must be shown. the possibility of resonant lock-in spin in the opposite sense to the expected steady-state spin can be anticipated by allowing for the missile's asymmetries. It is also apparent that there are induced roll moments for which the design steady-state spin will not occur under any launch conditions. If several stable equilibrium spins are possible, the one that occurs in flight can be determined by the orientation of the initial pitch angular velocity. Finally, the form of an induced pitch moment and its possible effect on the angular motion can be compensated to allow for precise placement of any asymetric rocket.

This is how the U.S. military is able to shove an ASM up a cricket's ass.

huh? in english please.

Basically, no rocket is perfect. Every rocket ever made has slight impurities; it's heavier on one side, the propellant is more flammable on one side, one rudder is shaped slightly different than another one. This makes the rocket spin and seem unstable. This spin is most noticable just before it hits because the spin becomes more and more out of control the further it has to fly. It's almost impossible to get a perfect launch in real life (expected steady-state spin), so the missile's imperfections are compensated for. Basically, they "put a spin" on the rocket to make it fly straight. the hard part is calculating how much of a spin to put on it. The initial pitch-angular velocity (direction, angle, speed) is used to calculate the resonant lock-in point for the rocket.

Sorry if this is confusing, rocket science usually is!

NOC117 %)<-----Picasso.

Any ?'s------>NOC117Overkill@aol

It works just like rifling spinning a bullet. The rocket is given a stabilizing spin that overpowers any imperfections it may have it you tried to launch it straight.

Well put, Fate.

The rocket can still roll left or right, or can drop. There's little chance of it flying upwards due to gravity, the trick is giving it the right amount of spin so that it doesn't spiral out of control.