A mechanism for maintaining a surface such as a landing pad in a desired orientation
with respect to a supporting surface includes a pair of columns that rotate with
respect to each other. The angle at which the columns engage, or the angle at which
the columns engage the surface and the supporting surface, are offset with respect
to a line perpendicular to the longitudinal axis of the cylinders. By selectively
rotating the columns with respect to each other and with respect to the supporting
surface, the tilt and orientation of the surface are adjusted.