diagonal cuts appearing in covering during flight
I have a 40 size great planes super sportster that I built from a kit two years ago. I have an 0S 40 fx engine on it and I typically fly it with a 10x6 or an 11x5 prop. It flies great, lands great, overall a wonderful airplane.
The last two times at the field I've noticed small diagonal cuts about 3/4 inch long appearing in the covering in the wing. The covering is monokote. One cut was midway out on the right wing, and the other was at the second to last rib bay. The cuts are appearing in open areas, ie not directly over the ribs, and I notice them only upon landing. I didn't notice any performance issues on any flight. In fact, the most recent cut appeared during one of four flights on a given day, and I didn't notice it until loading it up at the end of the day. I've covered them with clear plastic tape as a repair and have not had a problem.
I'm curious as to why these cuts might appear.