My Advance glider has winglets.  Advance claims the reduction in…

My Advance glider has winglets.  Advance claims the reduction in tip drag “corresponds to a glide ratio improvement of 1.5%”.  No way … maybe for a computer model with perfect flow, but not in the real world where the wingtip is soft and alignment is constantly shifting.  But anyway, I don’t mind them.  

I was looking at past flights from Tollhouse because I’ll be…

I was looking at past flights from Tollhouse because I’ll be flying there next weekend.  It’s amazing how thermals follow a collector (trapped area where air can heat) and trigger (edge that will launch the thermal). Sometimes it’s on a small scale (field or rock pile in sun surrounded by trees, power plant, canyon), and sometimes a larger scale (mountain ridge/peak) … but always a collector & trigger model.