Originally Posted by Larry DeCamp
I built a -3 because many considered it the most fun to fly RV. I bought 3B wings from salvage. I complained here that stick force was disappointing compared to expectations from glowing pireps. Jim Winings said the ailerons were smashed too small on the trailing edge and several folks say the 3B bellcrank is not the same as the original 3.
So, I analyzed the kinematics of the 3B vs -3 bellcrank and the 3B IS disadvantaged regarding stick input force. Then I built two new ailerons to address the thin trailing edge issue. As many are aware, some aerobatic ships use thick trailing edges and some jets use nearly squared trailing edges.
I was very careful on the new ailerons to assure the skin entered the curved trailing edge radius harmoniously without bumps or undercuts. The end ribs supplied by Vans defined this geometry. I was surprised to find the resulting trailing edge radius was larger than the plans called for. A 1/4" dowell fits easily inside the skin at the trailing edge. It was theorized that bigger could be better, so they are on the airplane.
Ironflight suggested I update my VAF posting when I had results. RVbuilder2002 considered my findings logical with no misleading or unsafe conclusions, so here it is:
The reduction in stick force is DRAMATIC, to the extent you can roll the ship with index finger pressure. Hands off the stick is dead stable subject to normal trim (heavy wing) characteristics. RVbuilder 2002 advised that the thicker trailing edge is known to reduce stick force at the potential reduction in roll rate. OK, I won't compete with F22's.
The -3B can be disappointing and awesome. Pay close attention to ailerons. I hope this helps a VAF participant.
Larry I have a RV7A built for me (here in Brazil it is legal).
I'm a bit disappointed with aileron input and control even compared with my former plane a RV9 that should roll much less than my new RV7A.
I do have aileron buffet in both sides when rolling, and I did have a heavy wing issue that was "fixed" by the builder.
I do not know I need to use rudder in rolls with the RV7 like I did not use rudder with my first plane that was a RV9. No buffets on the 9!
I'd really want to fix this roll rate (increase it) and stop the buffeting. Do you think I need more deflection on it? Maybe new ailerons (better shaped) also?
Can you contribute with any blue prints , plans , tips?
I very grateful any help I can get. I just think the way it is is not the way it was designed to be. Was an assembling error.