speculating in the field of an old profession such as ours. The fact that rather awkward 

 phenomena have been explained and found by more advanced theories is promising. 

 The paper by Kent [7] indicates some practical problems which should be 

 investigated. It will be quite a task to prove or to disprove his assertions as to optimum 

 form parameters and characteristics, and to extend the research to similar problems 

 suggested by practice. 



6. It is expected that the present freeboard regulations will crumble under the 

 impact of the present research impetus and that ship theory will contribute its share in 

 shaping more reasonable ones. This alone will have a most beneficial effect by increasing 

 the safety of small ships, the freeboard being a most decisive parameter. In the same 

 way, it is hoped that the safety regulations for passenger ships will profit from results 

 of research. 



7. By the introduction of the irregular seaway concept reliable information will 

 be obtained on the average performance of ships with respect to motions and resistance. 



The development of new instruments for measuring the seaway promises to 

 increase decisively the value of statistical investigations. 



The problem of service speed can be brought nearer to a solution, and the possi- 

 bility of appraising ship behavior in relation to other fundamental properties will be 

 promoted. For example, data will become available which permit one to decide when 

 stabilization is desirable. 



Statistics will furnish data on permissible acceleration and contribute to a better 

 understanding of safety limits, though, as mentioned earlier, knowledge from other 

 sources is indispensable to solve this problem. 



8. The overwhelming importance of damping has been frequently emphasized. 

 Already the present solution of the problem enables the designer to act on a rational 

 base when assigning proportions and forms, and further development will help us avoid 

 presently unknown pitfalls similar to those indicated by Ursell. There is not too much 

 hope for unexpected favorable solutions. 



9. We made the same statement earlier, especially with respect to exciting forces. 

 However, in the case of the roll motion where small changes in the decisive ship para- 

 meters can have large consequences, conditions may be different. Reference is made 

 to Grim's finding on the possibility of reducing the exciting roll moment by reasonable 

 form variations in the range of synchronism. 



10. The feasibility and efficiency of fins having been established, a wide field 

 is opened for their applications as means of control around all three axes. 



11. A better understanding of conditions leading to improved maneuverability 

 in a seaway will furnish design data to reach this goal and to increase thereby the safety 

 of ships. 



12. Although roll stabilization is developing successfully, the danger of capsizing, 

 or rather of reaching large angles of heel, still requires further investigations. Proposals 

 in this direction have been made over a considerable time but the work so far invested 

 does not correspond in any way to the importance of the task. 



13. The study of hydrodynamic impacts has now reached the degree of in- 

 tensity which corresponds to its fundamental importance. The continuation of research 

 on slamming and its extension to phenomena in a horizontal plane may decisively in- 

 fluence the design of high-speed vessels; it may lead to considerable progress in design- 

 ing important details like the forebody, superstructures, rudders, etc. 



14. Means to reduce motions will frequently lead to a reduction of resistance 

 and improvement of propulsion conditions. Furthermore, when reflection effects are 

 better understood suitable changes of form for influencing resistance directly may be 

 found. Old dreams of inventors to influence ship wave generation by fins at the bow 

 appear to be substantiated by recent investigations on performance in a seaway. 



15. Although possibly a refined determination of extraneous forces (pressures) 

 acting on the ship will not change basically the assumptions underlying the contempo- 

 rary strength calculations dealing with the ship as a girder the whole problem will be 



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