Projects Gerald's RCH Trainer moment of silence please

[Gerald]

I built it, wrecked it, fixed it and flew it, got over 2 hours of flight time! AND THEN..........
POP!

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The wing just gave up in a slow bank!

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OH Well! I have to build again!

 

[Tony]

Did the wing fold up on you? Let me know what the cause was and if I can create a fix for it. Sucks bro. Time to build a better one!

 

[Graham Lawrie]

Ouch Gerald

 

[Derek]

That sucks, Gerald! it was a great flyer. Probably just needs a pair of bamboo skewers or lengths of carbon fiber in the wing for strength. In the above pictures, it doesn't look like there was a spar of any kind. My RCH Trainer didn't have a spar in it either. I had almost 30 flights on it (quick rolls, hard loops) and then the wing folded while I was buddy boxing with my cousin.

So....build another one and incorporate some kind of spar in the wing.

 

[Gerald]

Tony, the wing failed right where the 2 halves are glued together. I think some kind of spar is needed for sure. Maybe a dowel rod, bbq skewers, carbon rod, arrow shaft, heck even a paint stirrer stick would help. The KFM3 is solid as a rock, I think the glue joint is the weak point. Like Derek posted above, I had done some rolls and loops, my boy flew it and he did the same, even inverted it a couple times. Then I was just slow cruizin in to a left bank turn and she folded up! But I am still happy! It was my first attempt to scratch build and it worked! I will admit it was not the first plane I flew but it was my very first build! I will build another!

 

[Tony]

Yeah, when I designed this plane, I did so for the beginner. And if you are putting dihedral in the wing, then it's very hard to put a spar there. But, I"m seeing more and more people folding the wing with the failure point being right there at the joint. I have a few options that I can do. One, forget the glue joint in the middle and put two on the outside edges. With this, I would get rid of dihedral, but could add polyhedral which is just as good if not better. And, you can put a spar in it, but it would not be needed unless the wing was damaged. Or, just say bye bye to the dihedral, use a straight wing from now on and use some kind of spar in there. NO matter, I will have a solution on the plans in a short time. Can't wait to see your next one!