Rotation sensing at 10 to the -10th earth rate

A 60 sq m Passive Resonant Ring Laser Gyroscope (PRRLG) has been developed, with a view to military optical rotation sensor applications, whose projected performance level renders it useful for error source studies, geophysical investigations, relativity experiments, and (potentially) gravity wave detection. The PRRLG is supported by a 450,000-lb reinforced concrete isolation test platform that is in turn floated on pneumatic isolators on a seismic base, and actively controlled to furnish vibration damping below 10 to the -8th g. Attention is given to planned experiments and to predicted and observed performance data.