# Axis specific velocity reduction

Hi, I have an actor with a physical body (just a collision box as a root, so that I can apply forces to it).
The Idea was to get the current velocity, transform it to a local space, reduce x,y,z by different amounts (bigger drag sideways), transform back to the world space and set the new velocity back.

So far, I’ve tried several ways of doing it, but each is failing. (more info here: [Solved] Axis specific Velocity Reduction - issue possibly in setLinearVelocity/math/local global - Blueprint - Epic Developer Community Forums)

The issue is that the velocity should be always smaller than the original one, but that isn’t always the case. When debugging, I’ve reduced local velocity, but the global one, after transform has gotten larger (possible bug? maybe?) and the outcome is that I am able to leave the “possibility space” as shown here:

I apply random force and get the initial velocity, which is shown by the blue arrow and the blue box. The black arrow represents the current velocity and you can clearly see, how the velocity doesn’t just get smaller, but actually gets bigger and leaves its possibility space. In the end, the ship moves in the opposite direction of the original velocity… this happens while I lerp the local velocity to zero.

What am I doing wrong?

The core, minimal code is this:

And I’ve found the culprit:

The issue was that each tick, the ship could be rotated differently, so the possibility space of the reduced vector changes. Violet velocity shows how previously impossible future velocity becomes possible, so with the optimal ship rotation, I am able to turn the vector fully around.

The sad thing is, that this actually isn’t an issue. It should act exacly like that. Car moving South will move north if only steering will be applied.