2-52 BOAT HULL DESIGN 



Decks: Sandwich construction; 2 plies cloth on top face, 1 ply 1-1/2 ounce mat, non- 

 structural core of variable thickness, 1 ply 1-1/2 ounce mat and 1 ply woven roving. 



Location Core Thickness 



Main Deck - Forward 



Main Deck - Cabin Sides 



Main Deck Aft of Cockpit 



Cabin Top - Lower Level 



Cabin Top - Upper Level 



Cockpit 



Interior Decks 



Built-in Bunks and Lockers in Forward Compartment: 4 plies woven roving. 



Bulkheads: 3/4 in. core with 1 ply cloth and 1 ply 1-1/2 ounce mat each side; 4 

 additional plies of cloth each side locally under mast. 



Design 



Shell Laminate: The laminate chosen is that referred to as Type A in this manual and 

 consists of: 1 ply cloth on the outboard face, 1 ply mat, and a varying number of plies of 

 woven roving. 



The laminate selection is based on the excellent laminate impact resistance to floating 

 objects as previously explained. 



The design head of water is taken to 12 in. above the deck edge measured from the 

 center of the panel, Table 2-2. 



Since the panels involved are all relatively long and narrow, the bending moment and 

 section modulus used are in each case taken for a 1 in. wide strip. This strip is considered 

 to act as a uniformly loaded, fixed ended beam of span equal to the distance between longitudinals. 



Because of the number of areas which must be checked, a tabular arrangement is used 

 for the calculations; Table 2-6. 



Shell Longitudinals: The shell longitudinals are designed as fixed ended beams to with- 

 stand the same design load as the shell they support. Hat section stiffeners are chosen 

 because of their greater efficiency due to the high section moduli required. The calcula- 

 tions have been arranged in tabular form for convenience, Table 2-7. The stiffeners shown 

 have been checked for shear and are adequate. For a typical shear calculation see Design 

 Example 2-3. 



Decks: All decks are to be of sandwich construction for rigidity. Type B sandwich is 

 used; Fig. 6 -53b. Each deck is checked for stress in the various elements, and for deflec- 

 tion. The core thickness required is determined for each criterion and the maximum 

 required is used. 



Forward Portion of Main Deck: The largest panel is between bulkhead No. 1 and the 

 forward end of the cabin trunk. 



Panel Dimensions: length = 5 ft. -6 in. ; width = 2 ft. -9 in. 



