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.