their full rated holding capacity. Instead, the anchors may hold only 

 enough to keep alive hopes of attaining greater capacities. Or, after 

 being dragged a limited distance, sufficient holding may develop to 

 justify, in the salvor's judgment, completing the full rigging 

 arrangement. When the pull-off loads are then applied, the anchors 

 begin to drag, and continue to displace with an undulating holding 

 capacity, the peak holding always being less than what is needed. 

 Further compounding the dragging problem is that new purchases must be 

 made on the beach gear leg as the anchor moves, a time-consuming and 

 exhausting endeavor. 



It is evident that other advantages than the ability to anchor in 

 hard seafloor portend from explosive anchors. Chief qualities that 

 could prove advantageous are the ability to embed directly into the 

 seafloor and the ability to resist loads from any direction immediately 

 without preset dragging. Less amounts of chain and wire rope would be 

 required. 



OPERATIONAL CRITERIA 



The objective of the program is to obtain a new anchor design that 

 will overcome the anchoring deficiency in coral seafloors and otherwise 

 enhance and broaden the Navy's salvage capabilities. Specific criteria 

 are that the anchor be: 



(1) directly embeddable into sand, coral, and mud seafloors without 

 the necessity of dragging to embed and set it; 



(2) capable of developing a holding capacity of 160,000 pounds 

 horizontal force measured at the hawser of the salvage vessel; 



(3) be operational and suitable for use in water depths of 50 to 

 500 feet; 



(4) practicable for use aboard standard U. S. Navy vessels of the 

 ATF, ARS, ASR, and ATS classes in conditions to sea state 4 without the 

 necessity of ship alterations. Auxiliary stowage and handling gear is 

 permissible. 



EXPLOSIVE ANCHORS - HISTORY 



The term "explosive anchor" has been commonly adopted to designate 

 a type of anchor that is propelled into the seafloor at high velocity by 

 virtue of a rapidly expanding propellant in a gun barrel. Explosive 

 anchors have been under development for over a decade. 



At the inception of the explosive salvage anchor program, they had 

 evolved into two basic types. One type with extensible flukes was being 

 marketed commercially in two sizes with rated capacities of 5 and 10 kips, 

 Figure 1. A second type with a shield-shaped anchor-projectile was 

 being marketed commercially by a different company in sizes with rated 

 capacities of 5, 10, and 50 kips, Figure 2. The U. S. Army Mobility 



