DEPTH 

 CHANGE 



CABLE 



TO 



SHIP 



PACKING NUT 



PRESSURE 



CHANGE 



— DUE 



TO 



DEPTH 



CHANGE 



WATERTIGHT BOX 



Figure 4 . Depth s ens o r mechan i c al details 



DEPTH CHANGES CAUSED BY 

 SHIP MOTION 



t-D 



COMPOSITE ERROR SIGNAL DEVELOPED 

 BY SENSOR IS PROPORTIONAL TO 



RESULTANT VERTICAL MOTION 

 DUE TO PITCH, ROLL, AND HEAVE 



SENSOR 



(PRESSURE SENSITIVE LOCATION: 

 HALF WAVELENGTH BELOW 

 SURFACE WAVES) 



LOWERED EQUIPMENT 



Figure 5. Depth sensor location and development 

 of error signal. 



10 



