I built my Lazy Bee a long time ago and have had this same problem ever since my maiden flight. It flys fine but once in a while if it starts to point down and maybe on any other airplane start to decend slightly, this one will pretty much do a nose dive and scare me to death. I have always been able to pull it out thank the Lord but, why does it do this? Other than this, its a great very slow floater. I built it as an extended wing Bee. I thought maybe my incenence or however you spell it might be a bit off as in the leading edge of my wing being lower than my trailing edge. Has anyone else had this problem with any other plane?