Lawn darting your Big Daddy is a right of passage, a great honor. You love it so much and fly it so much that sooner or later you are going to do something stupid, a part is going to fail, or a combination of factors will lead to a lawn dart. It is a stubby rocket with a big nose cone and shoulder on a thin LPR tube with LPR components. Why should I not expect nothing less than awesome perfection? With the thousands of BP SU motors I have used the only ejection failure was in my first Big Daddy and it lawn darted. With Der Grosser Vatti I had driven all that way and by Jove I was going to launch it, blast the wind! An E9 4 that had a bit of a wimpy ejection (The top clay plug was about 2/3 in tact) coupled with the wind and a highly arched flight path that resulted in a lawn dart. The Horror. Time to use the recovered fin can from Der GV and my repaired first Big Daddy for a hacked together two stager! Now that was only a semi-stupid idea because I was just on the edge of what the D12-0 could lift. Tried two flights and got mud on the nose cone both times. Had to retire it even though the Pad Fuehrer thought I could get it to work, I was just too scared. Now is it just my stupidity, expectations, poor maintenance/techniques or bad luck? NO. It has to be a fundamental design flaw!