SI 



Tests ac Sea 



Tests at sea, performed In water 66 feet deep, were undertaken to 

 deteralne the effectiveness of the water brake jnd to test Kaodllng 

 characteristics of the device at sea. The effectiveness of the water 

 brake is crucial to control of the rate of ascent of the device when 

 the bag is inflated. The aessenger line oust be employed to Activale 

 the brake. 



The four ascent laode^i tested were: 



1. Release of the device at the bottoa without increasing inherent 

 buoyancy and without ecyloying the ressenger line. 



2. Release without increasing buoyancy but with es^loynsent of 

 the Biessenger line. 



3. Release with cooplete bag Inflation but without line emplosTaent. 



4. Release with naxlicuia buoyancy and with the line eraployed. 



Test results indicated that the water brake used ia tests 2 and i 

 effectively liaited the ascent velocitv of the device. The ascent rates 

 of these tests w«re significantly lower than asce-nt rates of tests 1 and 

 3. The ascent rates observed in tests 2 and 4 would not endanger 

 personnel or equipment. Divers found the device was easily handled and 

 operated in the open sea in the absence of strong currents and heavy 

 surf conditions. 



DISCUSSION 



The following observations ---ere noted during the testing program and 

 should be considered in production design. 



The protQt>'pe device used in these tests had to be handled with 

 care because the nethods used in assembling the fiber glass structure 

 are not retonnented for production nodels. It was built to test a 

 concept anc can not take extrene abuse, such as dropping it into the 

 water from the deck of craft, but should be lowered into the water 

 by line. Future production r.odels can be constructed to withstand 

 rough treatc^nt. 



During tha program insertion and extraction of the scuba bottles was 

 facilitated by rotating then during the process. Future aodels sliould 

 ease the feature. 



The messenger line must be neatly level-wound on the reel (under 

 slight tension) to prevent its binding between underlying wraps when 

 a strain is taken. If binding occurs it could prevent the line fron 

 being payed out and abort an ascrnr. . To assure that the line regains 

 firmly wound on the reel, a small stopper line should be passed through" 

 the two holes provided for locking the lower flange of the reel to 

 prevent its turning. After the reel has been secured In this aanner. 



