Move the object down while it rotates

So im trying to rotate the object and then move it down while it rotates.But for some reason it does not want to move down like i want it too.

void FixedUpdate()

       rigidbody.velocity = new Vector3(0,-10,0);

       localTrans.RotateAround (,rotation_axis, 100 * Time.deltaTime);

       localTrans.rotation = Quaternion.identity;

Help me please.Thank you.

If you remove the rotation bits does it fall correctly?

It could be that you need to use rigidbody.MoveRotation or rigidbody.ApplyTorque to make the physics rotate the object. Directly setting the transform may be causing problems, but I couldn’t say without testing it.