filled with air its deck line is horizon- 

 tal and co-planar with the deck level 

 of the vessel. When partially flooded 

 the stern end sinks some 1 7 degrees 

 leading into the water. The deck is 

 fitted with rails and a carriage into 

 which the skids of PISCES III fit. The 

 carriage is moved along the rails by a 

 winch and drag line arrangement. 

 When the submersible is on board the 

 support vessel, the carriage is fully 

 fonvard and locked rigidly in place. 

 To launch the submersible, sufficient 

 water is allowed to flood into the 

 ramp section to submerge its stern end 

 some ten feet below the surface. 



The carriage is allowed to run aft 

 until the submersible floats free. To 

 recover, a line is used to haul the 

 submersible into the carriage which is 

 then drawn fully forward. The water is 

 blown out of the ramp section which 

 then returns to the horizontal. 



The stern end of the ramp section is 

 restrained by shock absorbing preven- 

 ters which, ivhile protecting the ramp 

 from damage, permit it to synchronize 

 relatively well with prevailing wave 

 action. Recoveries in seas ivith tvave 

 amplitudes of up to 3.5 meters have 

 been accomplished.^^ 



Docking Well Lift (Fig. 12.12): The only 

 submersible which routinely employs a well 

 lift or LSD-type concept for launch/retrieval 

 is the U.S. Navy's TRIESTE II. The system 

 is simple in concept but complex in practice. 

 The support ship WHITESANDS floods down 

 (25 feet is maximum ior ARD-12) to a depth 

 where TRIESTE II is afloat; prior to this 11 

 restraining lines are attached. One is a bow 

 line which later serves as a tow line. Four 

 lines on each side are passed aft as the 

 vehicle exits the WHITESANDS, and two 

 lines are held by two handling boats which 

 pull TRIESTE II out of the well. The bathy- 

 scaph cannot use its own power because it is 

 completely deballasted of gasoline and shot 

 for launch and retrieval; this condition puts 

 all propellers above the waterline. As a gen- 

 eral operating procedure, if the prevailing 

 wavelength is shorter than the length of the 

 WHITESANDS no launching is conducted un- 



til either the wavelength increases or the sea 

 calms. The WHITESANDS has no propulsion 

 power and is towed by the USS APACHE 

 (ATF-67). 



Catamaran-Submersible Surfaced (Fig. 

 12.12): ALVIl\''s launch/retrieval system uses 

 this approach. It differs from the DSRV cata- 

 maran system in that the DSRV mates with 

 its lifting cradle while submerged; ALVIN 

 mates while surfaced. During launch LULU 

 is laying to with her bow into the sea, ALVIN 

 is then lowered between the hulls on LULLfs 

 cable-suspended cradle until it is floating 

 and the cradle is brought to rest some 8 feet 

 below ALVIN''s skegs. Six steadying lines, 

 three on each side, are passed aft as ALVIN 

 clears the catamaran. Divers aboard the sub- 

 mersible are used to cast off lines and con- 

 duct pre-dive checks. Retrieval is accom- 

 plished in the reverse fashion with ALVIN 

 maneuvering into the catamaran. The opera- 

 tor standing in the submersible's sail directs 

 the entire launch/retrieval operation. Clear- 

 ance between ALVIN and the hulls is about 

 4.5 feet on each side, which constitutes the 

 major hazard when sea state is high. 

 Launch/retrieval has been conducted up to 

 sea state 4. 



Catamaran-Submersible Submerged (Fig. 

 12.12): Though it has not been field tested at 

 present, the DSRVs can be launched/re- 

 trieved on the surface in an ALVIN-like fash- 

 ion or retrieved below the surface. For sub- 

 surface retrieval the catamaran lowers the 

 cradle approximately 100 feet below the sur- 

 face and, through the use of guide arms and 

 a television system on the platform, the 

 DSRV positions itself on the cradle and is 

 hoisted to the surface. The purpose here is to 

 avoid the problems associated with sea state. 

 Subsurface launch and recovery in sea state 

 3 is considered possible. 



Open Stern Well (Fig. 12.13): This system 

 is employed by Lockheed's DEEP QUEST 

 and is similar to the ALVIN catamaran pro- 

 cedure. Within the 62-foot-long, 25-foot-wide 

 open well is a hydraulically-powered elevator 

 platform, 28 feet long and 23 feet wide, capa- 

 ble of lifting 60 long tons. Two handling lines 

 are attached on each side to assure that the 

 submersible does not collide with the sides of 

 the well or the forward bulkhead. Unlike 



601 



