Figure 7. Response ratio for 40,000-pound load and 6,000-foot wire at 5% rate, showing 

 effect of load damping (D^^). 



SYSTEM DESCRIPTION 



The MCLS is a passive system designed to 

 decouple ship motion from the payload. This 

 decoupling is accomplished by support of the load on 

 a spring whose resonant frequency is significantly 

 lower than the ship-motion frequencies that will be 

 encountered. The system consists of five functional 

 components: (1) the motion-compensation assembly, 

 designed to decouple the payload from ship motion; 

 (2) the traction unit to pay out and haul in the load 

 line; (3) the diesel-hydraulic power source to provide 

 all the power for system operation; (4) the operator- 

 control section; and (5) the takeup or cable-storage 

 reel to store the unused portion of the load-support 

 cable. 



These five components of the complete MCLS 

 are contained in two separate units. The motion- 

 compensating/traction unit (left in Figure 13) 

 includes the passive compensation assembly, the 

 traction winch, the diesel-hydraulic power source, 

 and the operator controls for the system. The cable- 

 storage reel is separate and is shown on the right in 

 Figure 13. Additional details of these two units are 

 shown in F'igures 14 and 15. 



Motion-Compensating Equipment 



The boom of the motion-compensating 

 equipment is pivoted at one end, has the payload lift 

 line suspended from the other end, and is supported 



