Specifications and requirements: 



(1) Contain a mechanism which will open and close 

 net on command. 



(2) Permit installation of conventional flowmeter. 



(3) Permit simultaneous use at intervals along the 

 towing wire. 



(4) Opening and closing of nets, when more than 

 one net is used in series, should be simultan- 

 eous to within ±1 min. per 100 m. of towing 

 cable length. 



(5) The opening and closing events on each net shall 

 be automatically recorded. 



(6) The opening-closing commands may be given 

 either from the vessel and/or by preprogramming. 



(7) Operate down to 2, 500 m. and from 1/2 to 3 

 knots. 



1.3220 High Speed Plankton Sampler Frame (75) 



Purpose: To collect at high speed a quantitative plank- 

 ton and larval sample at a specified depth and to 

 measure the environmental parameters encountered. 

 Specifications and requirements: 



(1) Net to open and close on signal fronn ship. 



(2) Mouth openings of from 2 to 20 cm. diameter to 

 be provided either adjustably or interchangeably 

 before tow. 



(3) To accept all or any of the environmental para- 

 meter sensors. 



(4) To measure volume of water filtered to within 



±5%. 



(5) So constructed to permit simultaneous use at 

 intervals along towing wire. 



(6) To operate down to 500 m. and from 5 to 15 

 knots. 



1.3300 NEKTON 



1.3310 High Speed Nekton Net (50) 



Purpose: To improve present designs of collecting 



nets which will quantitatively sample nekton. 

 Specifications and requirements: 



(1) Range: to 500 m. 



(2) To fish at desired depth controllable to within 



3 m. 



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