Attachment of Equipment to the Interior of the Capsule. The interior 

 of the capsule must contain certain subsystems that are needed to support the 

 life of the crew and to allow them to control effectively the operation of 

 externally located subsystems. These subsystems give the capsule vertical or 

 horizontal mobility, and possibly the ability to perform work by the use of 

 external manipulators. Asa minimum, such subsystems located in the interior 

 of the capsule would consist of life-support equipment, seats, control console, 

 emergency power supply, communication gear, and cameras. All of this equip- 

 ment must be securely attached to some rigid support that would prevent it 

 from being tossed around during launch and retrieval operations on the ocean 

 surface. 



When pressure-resistant capsules are of steel, securing such equipment 

 poses no design problem as the necessary brackets or framework can be directly 

 attached to the steel capsule by means of bolts or welding. A different case 

 presents itself for the acrylic plastic capsule. Since welding or bolting to the 

 interior capsule wall is not permissible, other ways had to be considered for 

 the securing of equipment. After considerable thought was given to this prob- 

 lem, four different approaches were arrived at for securing of equipment on 

 the interior of the capsule: 



1 . The equipment was to be bolted to a floor that in turn was bonded 

 to the wall of the capsule by means of a foamed-in-place plastic that completely 

 filled the spherical sector space enclosed between the flat circular floor and the 

 wall of the capsule below (Figure 10). The foamed-in-place plastic, for example 

 styrofoam, would distribute evenly in the capsule the weight of the equipment 

 and crew resting upon it. Because of the low modulus of elasticity of such 

 material, it would permit the diameter of the acrylic plastic capsule to shrink 

 considerably under hydrostatic loading without imposing a noticeable restraint. 

 The disadvantage of this arrangement lay in the permanency of the foamed-in- 

 place filler. Once the cavity below the floor was filled with foamed plastic, it 

 would become very difficult to perform any maintenance or modification to 

 the wiring and plumbing located below the floor. 



2. The equipment and the floor were to be bolted to an internal 

 cage that snugly fitted the interior dimensions of the acrylic plastic capsule 

 (Figure 1 1 ). Elastomeric spacers were to be inserted between the ribs of the 

 cage and the inner surface of the acrylic plastic capsule to permit the shrink- 

 age of the capsule's internal diameter without transfer of load to the cage. 

 The major shortcomings of this attachment method were the restriction of 

 panoramic vision, difficulty of assembling such a cage in the cramped interior 

 of the capsule from structural members small enough to pass through the 

 hatch, and reduction of usable interior space. 



20 



