Ah ok thanks, now it is close to a "realistic" movement.

I'm doing It like this:

(Angle is increased as done before)

Code:
xko :=xko - Cos(360-angle*(pi/180))*Speed;
yko :=yko + Sin(360-angle*(pi/180))*Speed;
but the movement in a 90AŹ? angle is not totally correct, maybe 10AŹ? more than it should be..

I have uploaded the thing i am working on here:
(it is a modified delphiGL example)
http://www.siedla-design.de/space.zip
Please have a short look..