The stiffeners were riveted to the skins using the back riveting technique. This worked well to minimize dents, but alignment was critical. A small number of the stiffener dimples showed some cracking near the rivet head. This was only in the stiffener, not the skin itself. VANs says that it is not a big concern if it is not the skin. They recommended to inspect these during the first annual inspection to make sure there is no issue.
