Cylic
You obviously don't have the dark art ! WE have found that the assumption that all the blades weigh the same was the start of the trouble. Once we got that sorted the rest was actually very easy. As said we then found problems with dampers with them. Discovered that it is not a stretch test that decides if it is ok it is measuring the damper after machine has been flying. If the damper doesn't recover to certain point we throw them away otherwise you get what you have described .
