This last weekend, I was cleaning out some junk from my shop and included was a 4*60 wing that was damaged. I finally decided not to try to repair it, and instead did a little off the cuff stress testing. I blocked up one end and stepped dead center. It took a fair amount of weight before it snapped. THis is after being damaged in a crash, having the LE jamed back about 1" where the the wing attaches to the fuselage, so the wing was already structualy damaged there. I then took a half wing and bridged it over the trash container, about a 24" span. I had to hammer it three or four times with my fist before it finally broke in half. I was susprised at how tough it was. I first leaned into it trying to push it in half, but that didn't work.
Wing strength has not been a problem with the 4*'s even though I saw one fail in flight. I found later that it had been crashed and repaired more than once, and it also had several hundred flights, so it was at EOL anyway.
Don
ORIGINAL: w8ye
ORIGINAL: Gray Beard
Here is a question that I have wondered about for a while. I build most of my planes from plans and mostly older designs. I was taught years ago that if you sheet a wing you can forget about the shear webs because the wing gets it's strength from the sheeting. On almost all of my older plans any wing that is sheeted there are no webs shown. Just wondering if anyone else has noticed this and what are there thoughts?? I have never had a wing fail but when building this is always at the back of my mind.
Gene
Very true but I have seen both in a wing.
The wings I've seen fail was a Four Star where the guy was being foolish and the wing breaks just where the center sheeting ends. Four Stars have webbing
The other plane was a Avistar were the guy was diving as fast as it would go and then pulling up and the wing broke at the dihedral brace.