S

ssisca

Member
I am finding that after fine tuning the trim tab cables my "Tab Down" deflection ranges B/T 32-35 degrees as measured with a digital protractor across the surface of both of my tabs. Better stated is that a reading on the outboard end of the tab is approx. 32 degrees and the inboard end is 35 degrees on the left tab and the same thing is true on the right tab but the readings are opposite approx. 32 degrees on the outboard end and 35 degrees on the inboard end. I would appreciate any thoughts.
 
HMMMMM

If you lay something very flat on the top of the tab like a back riveting plate or larger, can you see any twist or are they flat? I know mine had a slight bow to them when I installed them. I could only tell because the pin was not perfectly aligned as I installed the tab. You may be seeing something similiar.
Are you an engineer by chance? (very precise, I like that)


My opinion is that they are probably OK and that you should fly it to Oshkosh next year and we can all look at it there, do some formation flights to analyze the difference in airspeed and discuss other possibilities over a cool beverage at the RV-10 group campsite. :D
 
Scott most likely scored a direct hit with the twist unless there is enough binding in the hinge near the tip side to allow for a twist while it actuates. I doubt a 3 degrees difference would make a huge impact on the performance of the tab. Funny when I saw the thread name I thought for sure it would be addressing the difference between the amount of travel difference on the right vs. the left tab.

I look forward to being a flying -10 at OSH next year but I think I'll leave the formation flying to the military and those guys who made the 35 ship passes at OSH this year.
 
Perhaps whatever table you laid the edges of the trim tabs on while the pro-seal set is warped that amount?

Shouldn't matter, if you have alt. hold it will adjust the tabs until the VSI reads zero, no matter if there is a slight twist.

If you would like to test your math skills, measure the length of the tab, and use the angle difference to calculate the amount it is off (just kidding :D )
 
thanks to all who sent a reply. I was more curious then concerned about what I was finding with my tabs. I think what I have is a slight bow, not really a "twist" in the tabs due to the foam rib and prosel process that is used to form the shape. They look very good to the naked eye and in fact these are the second set I built because I was unhappy with the first set. I have considered fabricating my own set in a similar fashion as the elevator which to me seems like a nicer way to do it but from a performance stand point I see no benefit. Gonna just stay with what I got for now.
 
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