Figure 2. Top View of ALVIN on Ocean Floor. 



recovery. Also, equipment lists were developed, ships and craft to be assigned to the recovery 

 force were recommended, and modifications required for each of these vessels were determined. 



Initial Concepts 



The basic recovery concept was to (1) relocate ALVIN; (2) attach a lifting line with the 

 assistance of either an unmanned tethered device or a manned deep research vehicle; (3) winch 

 ALVIN to the surface with a lift ship; and (4) tow her to port or into shallow water for lifting 

 from the water. Careful consideration was given a number of factors that would bear signifi- 

 cantly on the recovery attempt. For example, the date of the recovery operation would be de- 

 pendent upon weather conditions. (The unsuccessful salvage attempt of November 1968 had 

 emphasized that the weather would be a major factor in the salvage attempt. From past weath- 

 er history, it was determined that the most favorable weather could be expected during July, 

 August, and September.) Also, the water depth and lift weight would dictate the type of lift 

 line, the recovery device, the surface support ship, and the lift ship that could be used. 



