terrye

Well Known Member
The RV-9(A) instructions state the horizontal (HS-910 tip) and vertical (VS-909 tip)stabilizer fiberglass tips must have their open ends filled (with fiberglass, fiberglass and balsa, fiberglass and foam) according to Figure 6-12. Nowhere in the drawings or printed instructions can I find any guidance on how much swing clearance to provide from the filled in tip to the elevators (HS-910 tip) or the rudder (VS-909 tip). That is, with the hinge rod ends adjusted to the values shown on the drawings. Also couldn't find any guidance on these forums.

What advice can the brain trust provide?
 
Terry,
I am not sure of the exact measurement of clearance, but I learned it is easier to build the surface up than make it too tight and try to increase the clearance.
I used balsa and fiberglass tape with West Systems epoxy. I think foam may be easier and that is how I am going to fill the other locations on the empenage - if I decide to do it!

I will see if I can find a photo or two.
 
I used blue foam with fiberglass.... Thought I had them fab'ed perfectly, but that was only when they were sitting on the bench. When I put em on, they were way too tight. I ended up with a tough sanding/grinding job to achieve a workable clearance. I think the "right" clearance I like the old definition of pornagraphy ... You know it when you see it. :)
 
I would recommend 1/8" clearance. I'm pretty sure that number is called out somewhere in the plans for the elevator/HS tip clearance.
 
I used 0.20 inch..... ice did not cause any elevator binding at 20K ft for my ONE icing encounter.
 
I usually work to make it match the gap between the horz. stab and the elevator counterbalance arm.
I think the designed gap at this location is 1/8".