Dear all,

Recently, I am trying to sum up the blade 1,2,3 out-of-plane moments using FAST. The results suggest me that the sum of the blade out-of-plane moments tends to a constant, and has a prefered constant angle (in a stationaty coordinate system). Is this result reasonable? If yes, is the fact caused by the teeter? Or I had some bug in my proceedure, which is the following:

My=M1*cos(A)+M2*cos(A+2*pi/3)+M3*cos(A+4*pi/3);
Mz=M1*sin(A)+M2

*sin(A+2*pi/3)+M3

*sin(A+4*pi/3);

M(out-of-plane)=(Mz^2+My^2)^0.5;

Direction=atan2(Mz/My,1)/pi*180;

Where M1, M2, M3 are Blade 1, 2, 3 out of plane moments(RootMyc1,RootMyc2,RootMyc3)

A is the Azimuth angle(Azimuth)

I appreciate any discussion and consideration. Thank you.

Sincerely,

Zhichao Yu

8/3/13