Requirements and Specifications; 



a. To be designed for "underway" operation and to perform 

 reliably at ship speeds of 0-15 knots and at operating depths of 



to 6, 000 feet. 



b. Net opening to be adjusted prior to lowering in water. 



c. Net to be designed so as to be opened and/or closed on sig- 

 nal from the ship. 



d. Net screen (mesh) size must be capable of being adjusted re- 

 nnotely fronn the ship, with an end view of achieving a minimum of 

 six (6) screen changes per cast. 



e. Water volume flow through net to be measured to an accuracy 

 of ±1 percent. 



f. This instrument should provide for attaching standard modu- 

 lar tennperature and depth sensors to the net frame to measure and 

 continuously transmiit this data to a recorder topside. The charac- 

 teristics of such standard sensors should be: 



(1) Depth Sensor: 



0-6,000 feet; ± 1 / 4% of full range 



Time Response: 95% response to a step function of 6 

 feet in 1 second. 



(2) Temperature: 



-2° to 35°C. ; ±0.1° C. 



Timie Response: 95% response to a step function of 

 1 C. in 1 second. 



g. Data Readout: 



(1) Proper form and type for direct input into the Master 

 Shipboard Data Logging and Processing System. 



Potential Users and Estimated Number of Units Which They May 

 Require : 



a. U. S. Navy (oceanographic survey ships, basic research 



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