NOTES 



1. To denote dimensionless values ample use is made of an asterisk. Where necessary the 

 length of reference is indicated by subscripts, for example, 



03*6 = aVB/g. 



The subscript L is omitted in expressions like 



w* = uVL/g. 



2. Two subscript notations are used to designate values pertaining to motions: 



2.1 x, y, z, *, \J/, 0, when a small number of motions is investigated; 



2.2 numbers 1, 2, 3, 4, 5, 6 in more general expressions. 



3. In the latter case added moments of inertia are denoted by mo- 

 Virtual generalized masses are denoted by a prime, e.g., 



m' 33 = m + '"33, m'n = J x + m«, etc. 



4. Two-dimensional mass and damping values are distinguished by a bar, e.g. m 33 , N 33 - 



DISCUSSION 



Paul Kaplan 



Since this talk was only a synopsis, and Dr. Weinblum expects the discussion 

 to amplify and expand many of his statements, I will attempt to consider some of the 

 work in hydrofoil craft and its extensions in greater detail. 



With regard to the analysis of motions of hydrofoil craft in a seaway, many 

 works of linearized theory exist with the use of quasi-steady forces in their derivation; 

 among them, one due to Dr. Weinblum. Comparison of the theoretical motions with 

 experiment, however, doesn't show good agreement, and presently, two alternate 

 developments, making use of the forces determined from the theory of unsteady motions, 

 are under investigation. Other work is being done on a study of scaling of the per- 

 formance of hydrofoil craft in waves. This concerns the change in wave sizes that a 

 hydrofoil craft can safely operate in when a change in size of the craft is made, with 

 the speed maintained relatively constant. These studies may contribute to a better 

 knowledge of the seaworthiness of hydrofoil craft, on which their future utilization 

 greatly depends. 



Another point about hydrofoil craft that makes them attractive for research 



98 



