TABLE 1 - GENERAL PHYSICAL CHARACTERISTICS OF THE 8-18-F 

 (CONFIGURATION A-1) INTEGRATED TOWLINE DESIGN 



Overall Characteristics 









2 

 Section shape 





8-18-F 





Chord, mm (in.) 



63.50 





(2.50) 



Maximum thickness, mm (in.) 



12.70 





(0.50) 



Weight in air, N/m (lb/ft) 



8.552 





(0.586) 



Weight in sea-water, N/m (lb/ft) 



2.877 





(0.193) 



Weight in fresh-water, N/m (lb/ft) 



2.977 





(0.204) 



Strength Member 









(Material - 80 percent parallel fiber "S" 

 glass/ 20 percent epoxy matrix) 









9 2 

 Cross-sectional area, mm (in. ) 



57.161 





(0.0886) 



Breaking strength, kN (lb) 



93.413 





(21000) 



Fairing 









(Main body material - Dupont Hypalon^'^) 









(Skin material - Dupont Hypalon impregnated 

 Dacron^ cloth D-400) 









Skin thickness, mm (in.) 



0.51 





(0.02) 



fibers which are bonded into recesses as shown in Figure 2. The portion of the 

 towline strength member separating the two conductor bundles is 1.6-mm (1/16- in.) 

 wide and extends 1.6 mm (1/16 in.) into the Hypalorfe^af terbody and acts as a key 

 to prevent lateral displacement of the afterbody relative to the strength member. 



Figure 3 illustrates the modified 8-18-F towline configurations, designated 

 B-1, C-1, C-2 and C-3, that also were evaluated in the towing basin. The trailing 

 edges of towlines B-1 and C-1 were truncated using an alternating bevel geometry. 

 The B-1 geometry was produced by beveling the trailing edge of the A-1 towline at 

 a 45-degree angle, alternating the bevel from side to side at 0.3-m (12-in.) 

 intervals. Configuration C-1 was produced by increasing the bevel depth of the 

 B-1 fairing. The B-1 and C-1 geometries reduce the original A-1 towline chord by 

 an average of approximately 9 and 16 percent, respectively. 



