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.
CROSS-REFERENCES TO RELATED APPLICATIONS
The present application is a continuation-in-part of U.S. patent application Ser. No. 11/039,548, filed Jan. 19, 2005 now U.S. Pat. No. 7,040,247, which claims the benefit of U.S. Provisional Application Ser. No. 60/539,922, filed Jan. 28, 2004, which is herein incorporated by reference.
