Experimental Determination of Unsteady Propeller Forces 



360 



330 



300 



270 



240 



210 



5 150 



120 



90 



60 — 



30 — 



O ._J 



EAR = 0.60 

 skewed 



CD 

 EAR = 1.20 



EAR = 0.60 



■% &- 



EAR = 0.30 



O Thrust 

 □ Torque 



1.0 



1.2 



1.4 



Advance Coefficient, J 



nTJ 



Fig. 26 - Phase angles of thrust and torque 



279 



