Bumper reminds me of one thing I did come up with at SoaringNV when we had a rope break and had trouble fishing the new rope through the tube. I started carrying in the towplane a 15 or 20' length (long enough to pass through the tube) length of the white plastic tubing used to plumb in refrigerator ice makers. It is rigid enough to push through the tube from either end and flexible enough to go around any bends and pass any joints you might have. Put some kind of hook in the end to pull the tow rope with and you're back in business pretty quickly. F