Lehman and Kaplan 



6. Lewis, F.M., "Vibratory Hydrodynamic Forces on Struts Located Forward 

 of a Propeller," MIT DSR 5-7851, June 1960 



7. Lewis, F.M., "Propeller-Vibration Forces," Trans. SNAME 71 (1963) 



8. O'Brien, T.P., "Some Effects of Blade Thickness Variation on Model- 

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9. Gurney, G.B., "An Analysis of Force Measurements," Pennsylvania State 

 Univ., Ordnance Research Laboratory Report TM 19.8841-24, Apr. 1963 



10. Lehman, A.F., "An Experimental Investigation of Propeller- Appendage 

 Interaction," Oceanics, Inc., Report 64-11, Jan. 1964 



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 Forces as Influenced by Appendage Attack Angle and Propeller Position," 

 Oceanics, Inc., Report 68-44, Jan. 1968 



12. Sugai, K., "On Vibratory Forces Induced on the Rudder Behind a Propel- 

 ler," Eleventh International Towing Tank Conference, The Society of Naval 

 Architects of Japan, Tokyo, Oct. 1966 



13. Kemp, N.H., and Sears, W.R., "Aerodynamic Interference Between Moving 

 Blade Rows," J. Aero. Sci. 20 (Sept. 1953) 



14. Milne- Thomson, L.M., "Theoretical Hydrodynamics," third edition, Mac- 

 Millan, New York, 1957 



15. Lehman, A.F., "An Experimental Investigation of Propeller Blade Thickness 

 and Appendage Asymmetry on Propeller- Appendage Interaction," Oceanics, 

 Inc., Report 66-24, July 1966 



16. Lehman, A.F., "Further Experimental Studies of Propeller Blade Thickness 

 and Appendage Asymmetry Effects on Propeller- Appendage Interaction," 

 Oceanics, Inc., Report 67-35, May 1967 



DISCUSSION 



R. Wereldsma 

 Netherlands Ship Model Basin 

 Wageningen, The Netherlands 



The authors made an interesting investigation of propeller induced append- 

 age forces, particularly interesting is the undulatory variation of the appendage 



230 



