PROJECTED BALLISTIC PERFORMANCE 



The Naval Ordnance Station, Indian Head, Maryland, selected smoke- 

 less propellant (M6) with 0.0579-inch (1.37 mm) web thickness (material 

 thickness between perforations) as the most suitable propellant for the 

 10K anchor.* This was based on desired performance criteria of: (1) max- 

 imum operating pressure of 50,000 psi (345 MPa) , (2) maximum acceleration 

 of 2,000 g's, and (3) minimum projectile velocity of 250 fps (76 mps) . 



A computer program for simulation of propellant -actuated anchor 

 performance was used to predict the 1 0K anchor ballistics at a range 

 of depths and charge weights. The results of the simulation are presented 

 graphically in Figures 6, 7, and 8. Using the plots (Figures 6 and 7) 

 of projectile velocity versus water depth for each projectile, charge 

 weight for peak performance (Figure 8) was determined with the limiting 

 condition of 2,000 g's acceleration for the 1 x 2-foot (31 x 61 -cm) 

 fluke and 50,000 psi (345 MPa) for the 2 x 2 -foot (61 x 61 -cm) fluke. 

 These charge weights are practically similar for both flukes. It appears 

 that a fluke larger than the 2 x 2-foot (61 x 61 -cm) fluke could be 

 effectively used with this gun system to improve anticipated performance 

 in clay seafloors. Once the system is used more, this decision can be 

 made more reliably. 



Projectile Velocity (FPS) 



Figure 6. 



Projectile velocity versus water depth for the GEL 10K 

 anchor at various charge weights. The projectile used is 

 the 173-pound, 2 x 2-foot fluke; the propellant is 

 M6, 0.0579-inch web. 



* J. H. Holden (1975). Technical Report IHTR 438: Propulsion 



system development for a 10, 000 -pound capacity embedment anchor. 

 Naval Ordnance Station, Indian Head, MD. 



8 



