'V 



INTRODCCTION 



The Sup>ervlsor of Salvage, under delegation of author i.:y by th« 

 Naval Ship Systems Cocnand, has pursued a progran intended to provide 

 the latest techniques and equipment to the Navy's salvage forces. The 

 Civil Engineering Laboratory (CEL) ,** Saval Construction Battalion Center, 

 Port Hueneise, California, sponsored hy the office of the Supervisor of 

 Salvage, has undertaken the study, design, and testing of a diver's lift 

 assist device, and this report docucents developrient of such a unit to 

 aid in fulfillment of this program. 



BACKGROUND 



Cfee prior developnent aimed at satisfying a salvage requireiaent was 

 the Hunley-Wischhoefer (K-V) Remote Recovery Svstec^ [1), a tvo-part sv5ten. 

 The first part, seen in Figure 1, consists of an assembly which has linited 

 adjustable buoyancy and which contains a packaged r^ssenger line. A r:ale 

 go-getter prod, attached to the bitter end of the messenger line, is hcused 

 in the lower end of the assembly, 'ihe second part is a fenale overshot. 

 Figure 2, that is used to guide a heavy-lift line down the messenger line 

 to the sale eo-getter prod when the prod has been attached to an object to 

 be salvaged. 



The H-W unit also provides divers with a i?.eans of transporting the 

 iiiale prod directly to :h; object of salvage and is capable of providing 

 United lift for transport or salvage of other objects. It is desicned Co 

 be har«iled in the water by one or tv-tj divers when it has been ad justed ~ -> 

 spproxiinately neutral buoyancy. 



'when the prod has been attached to the salvage object the H-W device 

 Is adjusted to the positive buoyant nwde, and the buoyancy section is re- 

 leased to rise to the surface, streaming the connecting packaged r^essesger 

 line. -At the surface, the buoy and iine are retrieved and brought aboard 

 ship where the line is threaded through the fenale overshot and secured. 

 The overshot is lowered by the heavy lifting line until It engages and locks 

 to the prod. The nessenger line Is then detached iron the prod and taken 

 aboard ship. The salvage lift can then be nade. 



The H-W device was tested and perforaed the assigned functions, as 

 reported in Reference 1. However, the testing revealed sonw undesirable 



* Foraerly Naval Civil Engineering Laboratory. 



^ The H-W system was designed as one cooponent of a three-part, 

 25-ton lift cap.bility, salvage system. 



