Hadler and He eke r 



Si««- 



Fig. 4 - Drawing of propeller 4002 



water surface. Normal open water-test procedures were used, i.e., the rpm 

 was held constant and the forward velocity ranged from to about 12 fps. Test 

 conditions are tabulated in Table 2. A three-to-one elliptical fairwater was 

 used in front of the propeller. It was noted in the semisubmerged condition that 

 a film of water came over the fairwater into the propeller disk. Comparisons 

 of the spray patterns in both the semisubmerged and hub-out conditions did not 

 seem to indicate any effect from this thin film of water. It was also noted in 

 running these tests at the low advance coefficients that the propeller and its hub 

 were generating a wave train which appeared to modify the submergence. 



The objective of the second phase of the experimental program was a more 

 detailed examination of all of the steady forces generated by a partially sub- 

 merged propeller for a number of speeds of advance. For this phase, Propeller 



1456 



