Some Hydrodynamic Aspects of Ship Maneuverability 



a surface ship and would not be expected for a submarine. Thus, I would cer- 

 tainly agree with Admiral Brard's statement that "generally speaking, the flow 

 can be idealized, but in a manner specific to each type of ship." As regards the 

 approximation of the lift force and moment by Taylor series or polynomials, I 

 feel that the important distinction from the mathematical viewpoint is that the 

 resulting expansions must be one-sided, with discontinuities in the even-order 

 derivatives, in order to account properly for the cross-flow drag effects. The 

 recent experimental results quoted by Admiral Brard, in modification of his 

 paper at the last Naval Hydrodynamics Symposium, are extremely interesting 

 and I look forward to the opportunity to study them in more detail when they are 

 published. 



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