Hi, what I am trying to do is create a targeting computer for a computer simulation. The end result is to find the vector in which a projectile must be fired to collide with the target. The target will either have a constant acceleration or none at all, and the projectile will instantaneously accelerate to it's velocity, and will have no acceleration after that. In this simulation there are no forces that interact with the objects. All of the information about the target will be available, along with the position and velocity of the projectile. The only thing that needs to be calculated is the vector between the point of collision and the projectile. I am assuming that the projectile will have sufficient velocity to collide with the target. My approach so far has been to use the kinematic equations to find this vector, by trying to solve for the z and y angles seperatly to the point of collision. Unfortunatly I can't get either of them down to a single variable to solve for! I either get stuck with the time from launch to collision and and an angle, or the final velocity of the target at collision and an angle! I have considered trying to use brute force to find the collision vectors, but I'm sure there is a better way. Can anyone please help me?