Fig. 12.31 A pelican hooK on the lift bndle o( STAR III. (NAVOCEANO) 



Fig. 12.32 U.S Navy safety hool<. (NAVOCEANO) 



long as 500 to 800 pounds of load are on the 

 hook. It provides positive visual identifica- 

 tion in the locked condition and a guide line 

 is led by hand into the submersible's lifting 

 ring, which is fairleaded back to the ship for 

 closure. During launch a release lanyard is 

 triggered from the ship at an appropriate 

 time, thereby negating the use of divers. 



The Link Hook (Fig. 12.33): Built into the 

 lifting structure of the L/iVK-designed sub- 

 mersibles (DEEP DIVER, SEA LINK and 

 others) is a housing into which an inverted 

 "T" shaped device, with a circular base, is 

 inserted. The edge of the circular base is 

 designed such that once the device is in- 

 serted and twisted it cannot be freed until 

 twisted back to the original position, thereby 

 avoiding inadvertent release. A further re- 



finement built into the JOHNSON SEA LINK 



system is shown in Figure 12.34. The in- 

 verted "U" shaped arm termination fits over 

 a device on the vehicle's topside and pro- 

 hibits it from rotating in the horizontal 

 plane once the submersible is snug against 

 the boom. 



TOWING 



Submersibles too large for at-sea launch/ 

 retrieval and not having access to an LSD for 

 support, must be towed to distant dive sites. 

 There are several disadvantages to towing: 

 Towing speed is slow (5-6 knots maximum); 

 working on the pitching topside of a sub- 

 mersible is difficult and, at times, dangerous 

 (the Federal Civil Service regulations pro- 



616 



