supports act in the same direction. Both systems are mounted to a flat machined

We describe a system of pneumatic piston mirror supports for use in an altitude over azimuth telescope which react to gravity and wind loading. A pressure controller provides dynamic compensation of variable wind loading and changes in the gravity loading as a result of altitude angle changes. An active air circulation system which ventilates every honeycomb cell can be implemented without interference from the mirror supports. The system can be expanded in principle to accomodate 8 m honeycomb mirrors.