In the past year I have been part of two accidents, both involving high rpm prop seperations. The firs was with an MVVS 40 and wood prop. At appx 15,000 the prop gave up and went in several diffrent directions, very fast. The second was a friends Rossi 60, It came up on the pipe, burped for some reason, threw the prop and spinner shattering the APC prop on the table part ,of which bounced back up cutting the back of his hand and a large welt. We now stand to the back of our planes to adjust high end, much safer.