A good friend of mine was a test pilot on the XV-15 in the '80's. He always thought that the materials of the day (engines, air frames, tubing, etc.) were right for the size of the XV-15 and that scaling up to the much larger V-22 was going to be very difficult.
He was right.
I would be interested to see the progress Bell has made. I was the Production Manager for the H-1Y/Z in 2002 and their composite scrap rate was horrendous.
