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Old 07-21-2009, 06:01 PM
  #13  
jetnuno
 
Join Date: Dec 2004
Location: Lisbon, PORTUGAL
Posts: 1,145
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Default RE: balancing a full flying stab

Hi

A while back I was sent an .xls file to find the center of the rotating axis of a flying stab (or canard). Still I am flying my F18 with unbalanced stabs and I have over 50 flights now. The buzz in the servos is big when the plane is in the ground and I was planning to find the rotating axis with that file.

Although, what is buzzing me is that the rotating axis is not the pressure center during flight and that is what kept me from balancing the stabs. In the end - I just don't know where to balance.

I want to balance in the pressure center and not in the c.g. of the stab. The PC, should be backwards of the rotating axis and the actual stab pivot of the F18 flying stab, is too much forward of both PC and rotating axis.

Imputs welcomed

[b]Rowing width 600 mm
Root rib [c] 500 mm
Outer rib [a] 300 mm
Edges rear differential [d] 100mm

Output data
t/4 plus 5% 322 mm
Spin axis of the root trailing edge rib [e] 276mm

Note: d is at angles> 90 ° is positive, at 90 ° is equal to 0, with <90 ° is negative, eg. -100


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