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I'm quite happy to build this plane on solidworks, a beautiful aircraft. but in the little knowledge that I have, some improvements can be made to safety, this airplane from what I have seen is not for instantaneous changes of direction, for those who want to build to start aerial maneuvers, I think it is necessary to make some small changes.

That's interesting - over 500 built, fully aerobatic....I would respectfully disagree with your assessment.

I really want to be wrong, and I think I am. but I have to state my point of view. I'm not talking bad about the aircraft, that aircraft is incredible. if I had the money to build one, this aircraft would certainly be one of my first options.

I've worked for two airframers. I don't share your concerns. Remember these are semi-monocoque airframes. The skins carry the loads. The bellcrank mount is pretty stiff. The wing and fuselage are also very torsionally stiff. There is nothing wrong with not having a rod end on every joint.

History of the airframe also gives evidence that the design is robust.

Sonex1517 wrote:That's interesting - over 500 built, fully aerobatic....I would respectfully disagree with your assessment.

We need a "Like" button on the site!

I guess somebody needs to talk to Tony ...

https://youtu.be/oP2P5XduWmQ?t=1374

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
166.7 hours / Status - Flying
Member # 109 - Florida Sonex Association

osvaldosurf wrote:1 - lengthen the 4 clips (w21-9) in the ribs 9 until they reach the rib 10, the only thing that holds the bellcrank aileron in place is the skin wing, I am of the opinion that the bellcrank aileron should be in the main spar.

I second the comments made elsewhere that this is a proven design, so it is very unlikely that this is a weak spot.

That said, yes, lengthening these members would indeed create a complete shear "box" to transfer spanwise shear to the main spar. It would be the sort of "undergraduate Aircraft Structures 101" solution.

However, Pete Buck (the aircraft's structural engineer) knew what he was doing and again, it seems to work fine. :)

Ihab

Adding parts that are not absolutely necessary for their task, like rod ends, only adds additional failure points.

David A. Sonex TD CAMit 3300.

Also extra​ stuff adds weight and cost.

CAD-3D........Opinion..........Comment

I am a great believer in KISS (keep it simple stupid). Having been in the Van's movement (built and flew) for over 30 years I have seen too many builders/flyers that thought they knew more than Richard VanGrunvsen knew, and had to modify his design to make it better. More times than not it was not better and some times they ended up worse off. If you have a good designed airplane with a good track record.........leave it alone. If it doesn't meet YOUR expectations.......then that's fine......move on to another design that suits your needs better. Don't try to change this one.

One comment that someone offered , and I agree with........adding more parts and pieces to get the same outcome only exposes you to more chance of a failure point. Sometimes a "failure point" is a pain, an inconvenience and can be costly........but sometimes a "failure point" is catastrophic and fatal.

At the risk of repeating myself.............KISS (keep it simple stupid).

Gordon..........Onex.......Hummel 2400

I finished sonex, very beautiful, this airplane, incredible airplane. I need you to send sonex links with beautiful paintings, the most beautiful I'll put on these models and post the photos here.

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