CHAPTER 76 



The Design of Special Hull Forms and 

 Special-Purpose Craft 



Classification of Special Hull Forms and 



Special-Purpose Craft 750 76.18 



The Design of Fine, Slender Hulls; Canoes, 76.19 



Racing Shells, and Fast Launches . . . 752 

 Ultra-High-Specd Displacement Types . . 754 76.20 

 Long, Narrow, Blunt-Ended Vessels; Great 76.21 



Lakes Cargo Carriers 755 76.22 



The Design of Dry-Cargo Vessels with Box- 76.23 



Shaped Holds 762 



The Design of Straight-Element Hulls . . 762 76.24 

 Partial Bibliography on Straight-Element 



Ship Designs 764 



Drawing Ship Lines with Developable 76.25 



Surfaces 765 



Design of Discontinuous-Section Forms; 76.26 



BUsters and Bulges 768 



Vessels with Fat Hull Forms 770 76.27 



Requirements and Design Notes for Fishing 



Vessels 770 76.28 



Partial Modern Bibliography on Fishing 



Vessels 771 76.29 



Fireboats or Firefloats 774 76 . 30 



Distinguishing Design Features of Self- 



Propelled Dredges 777 76.31 



Self-Propelled Box-Shaped Vessels .... 779 76.32 



Self-Propelled Floating Drydocks 779 76.33 



Design of Temporary Bows for Emergency 



Running and Towing 781 



Floats for Pontoon Bridges 782 



Yacht-Design Requirements; Some Aspects 



of Sailing- Yacht Design 783 



Brief Bibliography on Sailing- Yacht Design 786 



Asymmetric Hull Forms 787 



Design Problems in Multiple-Hulled Craft . 788 

 Requirements for and References on Ferrj'- 



boats 790 



Characteristics of Propelling Plant and 

 Propulsion Devices for Double-Ended 



Vessels 792 



Design Notes for Ferryboat Hulls and 



Appendages 793 



Special Problems of Icebreakers and Ice- 

 ships 794 



Tabulated Data and References on Ice- 

 breakers 799 



Hydrodynamic Design Features of Amphib- 

 ians 806 



Vessels Designed for Beaching 808 



Some Hydrodynamic Design Problems 



Common to All Submarines 809 



Lightships or Light Vessels 814 



Life-Saving or Rescue Boats 816 



Special-Purpose Craft of the Future ... 818 



76.1 Classification of Special Hull Forms 

 and Special-Purpose Craft. The design pro- 

 cedure outlined in the previous chapters of Part 4 

 applies generally to all types of craft which float 

 on or in the water and which are either self- 

 propelled or towed. However, the design rules 

 presented in those chapters are intended mainly 

 for medium and large general-purpose ships of 

 not-too-extreme form. Design of small craft is 

 taken up in Chap. 77 following. The operating 

 requirements for other types of water craft, of 

 which there are legion, call for vessels especially 

 designed to meet them. They involve unusual 

 design problems, many of which do not occur 

 elsewhere. 



Fortunately, the possible variations in the 

 hydrodynamic features entering into the solution 

 of these design problems are by no means as 

 great as the many kinds and variations of water 



craft involved. These features may first be related 

 to the various kinds of liquid flow, as is done in 

 Part 1 of the book. The features are then adapted 

 to the flow, following which various typical com- 

 binations of hull and propulsion devices are 

 considered. It is thus possible to treat, in more or 

 less systematic fashion, the particular design 

 problems associated with the multitudinous hull 

 forms and special-purpose craft that are contin- 

 ually being placed before the "general practice" 

 ship and propeller designer. 



The variety of special-purpose craft may be 

 expected to increase in the future as long as 

 specialization in the transportation field continues. 

 However, the types and the details of Uquid flow 

 around these craft will inci'ease only as man's 

 knowledge of hydrodynamics increases, and as 

 active use is made of this knowledge. 



Although the designer of large vessels may for 



750 



