Mod to replace the trim wedge with removable tab

Bob Axsom · #1 10-05-2010, 02:12 AM

As I have modified the plane for speed the original wedge I installed became ineffective. This is mod I made to our RV-6A to provide a removable ground adjustable rudder trim tab. In a 138 statute mile race with 5 turns last Saturday (10-2-2010) the plane averaged 208 mph and the ball stayed centered in straight and level flight. The same condition was true in the flights from Fayetteville, Arkansas to Sherman Texas and back to participate in the race. I recommend considering something like this in the original build instead of the almost standard trim wedge in RV-6s.

Bob Axsom

Peterk · #2 10-05-2010, 09:08 AM

Bob,

nice. how did you decided where to put it (high/low)? and what makes it removable? thx.

Bob Axsom · #3 10-05-2010, 10:34 AM

I tried to get it down near the thrust line so it doesn't introduce any rolling force I guess but basically I put it near where I installed the wedge when I originally built the airplane and where I had some rudder damage from it hitting the ground when I put my 200 lbs on the step with a heavily loaded plane to help my wife out with little fuel in the tanks. The incident at Piqua, Ohio gave me the opportunity to make the change without fretting about damaging the paint.

To remove the tab I just remove the 5 screws.

Bob Axsom

SHIPCHIEF · #4 10-05-2010, 11:07 AM

I like the way you can take off the tab, give it a bit more bend or replace it with a new design then put it on. Too bad that isn't in the original plans. I would think a doubler plate and some plate nuts would have been easy to add at that point....but that was a long time ago, and very early in my learning curve. As a beginner, maybe it's best the way VAN designed it. Now that I can do this work more easily, it would be easy to go back and add something like this. I'm greatful that you share it.

az_gila · #5 10-05-2010, 12:54 PM

...one out of soft aluminum like some certified planes use?

Bob Axsom · #6 10-05-2010, 06:17 PM

I try to think these things out so I don't get stuck with another hard to change design. I certainly considered rivets as the initial easy way to go but for my changing airplane I thought the installation with screws offered the best solution. As always I'm looking for speed and while this configuration is better than the wedge it probably is not the ultimate solution. In my modifications I try not to put in anything that I cannot back out cleanly.

Bob Axsom