the greatest promise of being simple, reliable, and economically 

 feasible, primarily because a major cost of the system, the gun barrel 

 could be obtained by shortening surplus Army or Navy guns. 



Approach and Scope 



Development of the direct embedment anchor involved utilization of 

 existing components and simplified structural shapes, design of a rapid 

 keying anchor fluke to allow the most efficient use of penetration 

 energy, and an optimization study between seafloor soil conditions, 

 fluke behavior, and launcher system performance. 



The launcher system and the safe and arm device were developed for 

 NCEL by other Navy Laboratories. The remainder of the anchor system 

 was designed and fabricated at NCEL. 



This report provides a description of the anchor, documents the 

 results of the land testing program used to define launcher system 

 performance, and outlines the procedures involved in designing the 

 anchor. Included in appendices are a soil-anchor interaction analysis 

 to determine required sizes of flukes and an optimization study to 

 determine the correct propellant characteristics for proper performance 

 at any water depth to 20,000 feet. 



DESCRIPTION OF EQUIPMENT 



General 



The deep water anchor shown being lowered into the sea (Figure 1) 

 was conceived as an expendable hardware item. Therefore, every effort 

 was made to use simplified structural shapes and existing components 

 to achieve a design that could be inexpensively modified. The anchor 

 is about seven feet high and weighs about 1,800 pounds. It consists of 

 two major parts, a launch vehicle and a projectile which includes piston 

 and fluke. Three different flukes are needed to satisfy the realm of 

 anticipated seafloor conditions (sand, clay, and rock). The three-foot 

 long sand fluke and the five-foot long clay fluke are similarly con- 

 figured plate-like projectiles. A three-fin, three-foot long, 

 arrowhead-shaped projectile will be used for rock anchoring. 



Functional Description 



The anchor schematically illustrated in Figure 2 is designed to be 

 control-lowered to the seafloor and to be functional in water depths 

 from 100 feet to 20,000 feet. Above 100 feet safety switches prevent 

 activation. When a probe protruding 26 inches below the fluke tip con- 

 tacts the seafloor, the firing sequence is initiated. The projectile 

 (fluke/piston) is restrained from movement by the shear pin links 

 (modified tumbuckles) until pressure within the gun barrel reaches 

 3,000 psi. At this point the projectile which is connected to the main 



