And i put that in quotes because i know different people call them different things. Wing tip fins, winglets, hedrals (an- or di-; it's what i call them). I have been trying so very hard to create some planes without these that fly as good or better than ones with them and it usually comes up naught. I only have two right now in my pipeline that are working, but they do seem okay and have no tips/lets/hedrals. We had a paper aeroplane contest in Filey (small seaside toen in the uk) on the weekend. There were loads of different shaped planes some with wings somewithout. Mine had no wings as i wanted to make something streamlined with all the weight at the front. And...I won. Im pretty sure that its easir to move distribution of weight through having more paper at the front than trying to work out how to shift weight with wings.