I have twice, but I think that was my fault more than anything. As far as the tubing goes, it may cause a binding in the blades as they move in the blade grips. Keep in mind that the blades will still want to lead and track (I believe that's what it's called) as you fly. That tubing may keep that from happening and causing an imbalance in the head. If you get it to work let us know and get video of you flying it with that tubing in.