Canadian Hydrofoil Program. Hydrodynamics and Simulation 



DISCUSSION 



Christopher Hook 



Hydrofin 

 Bosham, Sussex, U. K. 



I listened to the two papers by MichaelEames given recently 

 at the Royal Institute of Naval Architects in London and I make no 

 apology for repeating here the specific question I put to Eames at the 

 end of his second Paper. 



In the discussion of hydrofoils in England there has been a 

 lot of talk about resonance and I asked Mr. Eames specifically if in 

 the course of the development work on the Canadian boat they had ever 

 encountered any resonance phenomena, because whether the damping 

 system be a diamond foil working basically on the Grunberg principle 

 or a mechanically highly damped system, the resonance effects are 

 going to be directly connected with the amount of damping. If the 

 speaker would enlarge on this I think it would be of interest to all the 

 listeners. 



REPLY TO DISCUSSION 



Rodney T. Schmitke 



Defence Research Establishment Atlantic 

 Dartmouth, Nova Scotia, Canada 



Figures 23 and 24 show that BRAS D'OR's pitch response 

 peaks at approximately . 2Hz, the natural frequency of the ship in 

 pitch. Response is fairly broad, however, and the peak is not pro- 

 nounced (low Q), so there is no resonance problem. 



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