prepare a form which groups together: 

 Structures: Pressure hull, exostructure, fair- 

 ings; 



Propulsion and Electrical Plants: Propellers, 

 thrusters, batteries; 



Communication and Control: Underwater 

 telephone, steering controls, radio; 

 Auxiliary Systems: High pressure air, ballast- 

 ing, life support; 



Outfit and Furnishings: Hull fitting, chairs, 

 paint; 



Crew and Instrumentation: Crew, scientific 

 and operational instruments, tools. 



An estimate is made of the weight, dis- 

 placement volume and centers of gravity and 

 buoyancy of each item within the preceding 

 group. When such calculations are made, the 

 elements of the vehicle must be adjusted in 

 size and placement until two conditions are 



nearly met: 1) The sum of all weights must 

 be equal to the weight of the water displaced 

 by all buoyant volumes; and 2) the resultant 

 center of gravity of all weights must be 

 below and in a vertical line with the result- 

 ant center of buoyancy. 



Rechnitzer and Gorman (1) treat in detail 

 the procedures for calculating submerged 

 displacement of various components and 

 housings used in submersibles. Final adjust- 

 ment to attain neutral submerged buoyancy 

 is made with fixed, positive (e.g., syntactic 

 foam) ballast or fixed negative (e.g., lead 

 weights) ballast either inside or outside the 

 pressure hull. 



Vincent and Stavovy (2) present figures for 

 the average weight of components within the 

 preceding list; these are as follows: 



Structures 65% 



TABLE 6.1 PRELIMINARY WEIGHT AND BUOYANCY ESTIMATES 



B.L. - Base Line 



F.P. - Forward Perpendicular 



VCG - Vertical Center of Gravity 

 LCG - Longitudinal Center of Gravity 



VCB - Vertical Center of Buoyancy 

 LCB - Longitudinal Center of Buoyancy 

 L.O. - Lockout 



280 



