RE: Wing tube failure at center due to holes drilled in tube
Here is a picture of the wing tube. The phenolic tube around the aluminum tube was also broken in half. The reason I used the screw into the tube was just to make it easier to align the tube. I remove the tube from the fuse and both wings for transport. When assembling, it is easier to get the tube positioned so that the ends of the tube are aligned with the holes in the bottom of the wings. I was using the method of connection whereby there is a #6 screw from the bottom of each wing in to the last inch of tube. This is the method recommended by the kit manufacturer (Carden) for retaining the wings on the tube. NOTE that Carden does NOT recommend drilling any holes in the middle like I did.